Simple Techniques To Increase Gas Mileage of Your Car
07-10-2007, 08:29 PM
#46
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
On Tue, 10 Jul 2007 22:52:01 +0000, Brian Smith wrote:
>
> "Hachiroku ????" <Trueno@AE86.gts> wrote in message
> news:TgIki.5140$V35.1567@trndny03...
>>
>> Also,brakes are cheaper (and easier) than a clutch.
>
> True.
>
>> Of course, I downshift 90% of the time...
>
> You don't need to use a clutch to shift gears. Just to pull away and
> to
> come to a stop.
I've only used that method when the cable broke or one of the cylinders
went bad.
Yeah, it works...sometimes...
>
> "Hachiroku ????" <Trueno@AE86.gts> wrote in message
> news:TgIki.5140$V35.1567@trndny03...
>>
>> Also,brakes are cheaper (and easier) than a clutch.
>
> True.
>
>> Of course, I downshift 90% of the time...
>
> You don't need to use a clutch to shift gears. Just to pull away and
> to
> come to a stop.
I've only used that method when the cable broke or one of the cylinders
went bad.
Yeah, it works...sometimes...
07-15-2007, 06:08 PM
#47
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:nOEki.2665$CJ4.1081@trndny08...
> gigelus2k3 wrote:
>
>> On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>> <"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>
>>>* Coast when possible and safe, rather than going back and forth between
>>>the gas and brake pedals.
>>
>>
>> What's up with all the advice to brake using downshifting instead of
>> coasting (manual tranny, of course)? I even heard this Sunday the two
>> clowns at cartalk claiming that downshifting is the way to braking
>> instead of bleeding off speed by only friction (when possible, of
>> course). Is there a downside to coasting?
>>
>> I remember trying braking using downshifting and my mileage went down
>> by about 15% (city driving, from 35 to 30). Why would I want this?
>>
>
>
> Using engine braking will virtually shut of the flow of fuel to the
> injectors, making the engine use less fuel than in coasting.
According to the ScanGauge readouts, it uses up to twice the fuel of
coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
dunno.
--
Phil
07-15-2007, 06:08 PM
#48
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:nOEki.2665$CJ4.1081@trndny08...
> gigelus2k3 wrote:
>
>> On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>> <"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>
>>>* Coast when possible and safe, rather than going back and forth between
>>>the gas and brake pedals.
>>
>>
>> What's up with all the advice to brake using downshifting instead of
>> coasting (manual tranny, of course)? I even heard this Sunday the two
>> clowns at cartalk claiming that downshifting is the way to braking
>> instead of bleeding off speed by only friction (when possible, of
>> course). Is there a downside to coasting?
>>
>> I remember trying braking using downshifting and my mileage went down
>> by about 15% (city driving, from 35 to 30). Why would I want this?
>>
>
>
> Using engine braking will virtually shut of the flow of fuel to the
> injectors, making the engine use less fuel than in coasting.
According to the ScanGauge readouts, it uses up to twice the fuel of
coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
dunno.
--
Phil
07-15-2007, 06:08 PM
#49
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:nOEki.2665$CJ4.1081@trndny08...
> gigelus2k3 wrote:
>
>> On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>> <"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>
>>>* Coast when possible and safe, rather than going back and forth between
>>>the gas and brake pedals.
>>
>>
>> What's up with all the advice to brake using downshifting instead of
>> coasting (manual tranny, of course)? I even heard this Sunday the two
>> clowns at cartalk claiming that downshifting is the way to braking
>> instead of bleeding off speed by only friction (when possible, of
>> course). Is there a downside to coasting?
>>
>> I remember trying braking using downshifting and my mileage went down
>> by about 15% (city driving, from 35 to 30). Why would I want this?
>>
>
>
> Using engine braking will virtually shut of the flow of fuel to the
> injectors, making the engine use less fuel than in coasting.
According to the ScanGauge readouts, it uses up to twice the fuel of
coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
dunno.
--
Phil
07-15-2007, 08:47 PM
#50
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Phil wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
07-15-2007, 08:47 PM
#51
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Phil wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
07-15-2007, 08:47 PM
#52
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Phil wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:nOEki.2665$CJ4.1081@trndny08...
>
>>gigelus2k3 wrote:
>>
>>
>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>
>>>
>>>>* Coast when possible and safe, rather than going back and forth between
>>>>the gas and brake pedals.
>>>
>>>
>>>What's up with all the advice to brake using downshifting instead of
>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>clowns at cartalk claiming that downshifting is the way to braking
>>>instead of bleeding off speed by only friction (when possible, of
>>>course). Is there a downside to coasting?
>>>
>>>I remember trying braking using downshifting and my mileage went down
>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>
>>
>>
>> Using engine braking will virtually shut of the flow of fuel to the
>>injectors, making the engine use less fuel than in coasting.
>
>
> According to the ScanGauge readouts, it uses up to twice the fuel of
> coasting when you downshift. For example, 0.7GPH is the fuel rate at idle.
> It will jump up to 1.2GPH if downshifted to 2nd at ~35mph. Shifting into
> neutral and braking will maintain the 0.7GPH. Maybe the ECU is lying, I
> dunno.
>
I was repeating what I knew of how EFI systems worked years ago. If
you are correct, then the Car Talk Clowns are completely, 100% wrong,
not just 75% wrong. ;-)
07-16-2007, 08:35 AM
#53
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
07-16-2007, 08:35 AM
#54
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
07-16-2007, 08:35 AM
#55
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
news:eezmi.2439$4J4.1750@trndny05...
> Phil wrote:
>> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>> news:nOEki.2665$CJ4.1081@trndny08...
>>
>>>gigelus2k3 wrote:
>>>
>>>
>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>
>>>>
>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>between
>>>>>the gas and brake pedals.
>>>>
>>>>
>>>>What's up with all the advice to brake using downshifting instead of
>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>instead of bleeding off speed by only friction (when possible, of
>>>>course). Is there a downside to coasting?
>>>>
>>>>I remember trying braking using downshifting and my mileage went down
>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>
>>>
>>>
>>> Using engine braking will virtually shut of the flow of fuel to the
>>> injectors, making the engine use less fuel than in coasting.
>>
>>
>> According to the ScanGauge readouts, it uses up to twice the fuel of
>> coasting when you downshift. For example, 0.7GPH is the fuel rate at
>> idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>> Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>> ECU is lying, I dunno.
>>
>
> I was repeating what I knew of how EFI systems worked years ago. If you
> are correct, then the Car Talk Clowns are completely, 100% wrong, not just
> 75% wrong. ;-)
>
I don't think they got that wrong; it's practically mandated by emission
concerns. Cleaning up marginal combustion conditions is a lot tougher than
turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
truck I could feel the cutout happening on descents. The engine drag would
suddenly increase at some RPM level and then switch back when the RPMs
dropped.
In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
engine operation compared to the OBDII bus info, and it's apparent the bus
info is not quite right all the time. In particular, the injector open time
is way off at idle (the same indications that would be used to calculate
idle fuel flow). That makes sense as the info is there for diagnostic
purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
you say, the ECU is telling little white lies.
Mike
07-17-2007, 05:36 AM
#56
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Michael Pardee wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
07-17-2007, 05:36 AM
#57
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Michael Pardee wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
07-17-2007, 05:36 AM
#58
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
Michael Pardee wrote:
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
> "mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
> news:eezmi.2439$4J4.1750@trndny05...
>
>>Phil wrote:
>>
>>>"mjc13<REMOVETHIS> @verizon.net>" <"mjc13<REMOVETHIS> wrote in message
>>>news:nOEki.2665$CJ4.1081@trndny08...
>>>
>>>
>>>>gigelus2k3 wrote:
>>>>
>>>>
>>>>
>>>>>On Jul 9, 8:45 pm, "mjc13<REMOVETHIS>"
>>>>><"mjc13<REMOVETHIS>"@verizon.net> wrote:
>>>>>
>>>>>
>>>>>
>>>>>>* Coast when possible and safe, rather than going back and forth
>>>>>>between
>>>>>>the gas and brake pedals.
>>>>>
>>>>>
>>>>>What's up with all the advice to brake using downshifting instead of
>>>>>coasting (manual tranny, of course)? I even heard this Sunday the two
>>>>>clowns at cartalk claiming that downshifting is the way to braking
>>>>>instead of bleeding off speed by only friction (when possible, of
>>>>>course). Is there a downside to coasting?
>>>>>
>>>>>I remember trying braking using downshifting and my mileage went down
>>>>>by about 15% (city driving, from 35 to 30). Why would I want this?
>>>>>
>>>>
>>>>
>>>> Using engine braking will virtually shut of the flow of fuel to the
>>>>injectors, making the engine use less fuel than in coasting.
>>>
>>>
>>>According to the ScanGauge readouts, it uses up to twice the fuel of
>>>coasting when you downshift. For example, 0.7GPH is the fuel rate at
>>>idle. It will jump up to 1.2GPH if downshifted to 2nd at ~35mph.
>>>Shifting into neutral and braking will maintain the 0.7GPH. Maybe the
>>>ECU is lying, I dunno.
>>>
>>
>> I was repeating what I knew of how EFI systems worked years ago. If you
>>are correct, then the Car Talk Clowns are completely, 100% wrong, not just
>>75% wrong. ;-)
>>
>
>
> I don't think they got that wrong; it's practically mandated by emission
> concerns. Cleaning up marginal combustion conditions is a lot tougher than
> turning off the fuel altogether when it isn't needed. On my 1993 Chevy work
> truck I could feel the cutout happening on descents. The engine drag would
> suddenly increase at some RPM level and then switch back when the RPMs
> dropped.
>
> In the Yahoo! Prius-Technical-Stuff forum there is a lot of discussion about
> engine operation compared to the OBDII bus info, and it's apparent the bus
> info is not quite right all the time. In particular, the injector open time
> is way off at idle (the same indications that would be used to calculate
> idle fuel flow). That makes sense as the info is there for diagnostic
> purposes. Personally, I suspect the ScanGuage is operating on bogus data. As
> you say, the ECU is telling little white lies.
>
> Mike
>
>
I didn't say that, but it sounds apt. I remember that the last of
the street-legal two-stroke motorcycles used a novel way to get through
the EPA emissions cycle: IIRC a butterfly valve blocked off the exhaust
port(s) when the throttle was closed. With fuel injection it's even
easier to virtually shut off the fuel flow for deceleration...
07-23-2007, 10:06 PM
#59
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
In article <1183974981.889479.289940@o11g2000prd.googlegroups .com>,
vcpjitwanhwe@yahoo.com wrote:
> You can have a huge potential saving of your car fuel consumption
> without paying one extra penny in expensive Car Modification or
> hunting for best Fuel-Saving Vehicle. It's easy if you can learn the
> mechanics of driving efficiently..
> Here are some of the priceless tips you should arm yourself with:
> Discover why gas stations may be overcharging you and learn what to do
> to avoid overpaying for the gas you did not use.
Save $17 and read your cars owners manual.
Also Google "gas saving driving tips".
vcpjitwanhwe@yahoo.com wrote:
> You can have a huge potential saving of your car fuel consumption
> without paying one extra penny in expensive Car Modification or
> hunting for best Fuel-Saving Vehicle. It's easy if you can learn the
> mechanics of driving efficiently..
> Here are some of the priceless tips you should arm yourself with:
> Discover why gas stations may be overcharging you and learn what to do
> to avoid overpaying for the gas you did not use.
Save $17 and read your cars owners manual.
Also Google "gas saving driving tips".
07-23-2007, 10:06 PM
#60
Guest
Posts: n/a
Re: Simple Techniques To Increase Gas Mileage of Your Car
In article <1183974981.889479.289940@o11g2000prd.googlegroups .com>,
vcpjitwanhwe@yahoo.com wrote:
> You can have a huge potential saving of your car fuel consumption
> without paying one extra penny in expensive Car Modification or
> hunting for best Fuel-Saving Vehicle. It's easy if you can learn the
> mechanics of driving efficiently..
> Here are some of the priceless tips you should arm yourself with:
> Discover why gas stations may be overcharging you and learn what to do
> to avoid overpaying for the gas you did not use.
Save $17 and read your cars owners manual.
Also Google "gas saving driving tips".
vcpjitwanhwe@yahoo.com wrote:
> You can have a huge potential saving of your car fuel consumption
> without paying one extra penny in expensive Car Modification or
> hunting for best Fuel-Saving Vehicle. It's easy if you can learn the
> mechanics of driving efficiently..
> Here are some of the priceless tips you should arm yourself with:
> Discover why gas stations may be overcharging you and learn what to do
> to avoid overpaying for the gas you did not use.
Save $17 and read your cars owners manual.
Also Google "gas saving driving tips".