Re: Adding an O2 sensor?
 

Matt Ion wrote:
> John Horner wrote:
>> Jim Yanik wrote:
>>
>>>
>>> Well,the desired end result is complete combustion(a clean
>>> exhaust),and exhaust O2 content is an indication of how well that's
>>> happening.
>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>> feedback corrects for it.it also allows for individual cylinders'
>>> injectors to be corrected,compensating for differing air flow thru
>>> the cylinders.They are not necessarily all equal!)
>>>
>>
>> Uh, hold on there. Few if any modern fuel injection systems monitor
>> each cylinder and adjust them independently. At best you have one
>> O2 sensor per bank on a multi-head engine. The ECU has no
>> information about individual cylinders.
>
> Well, I can't claim to know exactly how these systems DO work, but I can
> hypothesize that it wouldn't be all that difficult for the ECU to get an
> idea what's going on with each cylinder individually.

it's already done to some extent - angular velocity for each power
stroke is measured, so any cylinder not producing the same "oomph" as
the others gets individually tuned.

> Given timing
> input, it will know which cylinder is firing when, and a subsequent
> change in the O2 sensor reading is pretty easy to correlate to that
> cylinder.
>
> As O2 sensor input is split up to separate groups of cylinders, as has
> already been discussed here, such calculations become even easier...
>

Re: Adding an O2 sensor?
 

jim beam <spamvortex@bad.example.net> wrote in
news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:

> Matt Ion wrote:
>> John Horner wrote:
>>> Jim Yanik wrote:
>>>
>>>>
>>>> Well,the desired end result is complete combustion(a clean
>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>> happening.
>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>> feedback corrects for it.it also allows for individual cylinders'
>>>> injectors to be corrected,compensating for differing air flow thru
>>>> the cylinders.They are not necessarily all equal!)
>>>>
>>>
>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>> each cylinder and adjust them independently. At best you have one
>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>> information about individual cylinders.
>>
>> Well, I can't claim to know exactly how these systems DO work, but I
>> can hypothesize that it wouldn't be all that difficult for the ECU to
>> get an idea what's going on with each cylinder individually.
>
> it's already done to some extent - angular velocity for each power
> stroke is measured, so any cylinder not producing the same "oomph" as
> the others gets individually tuned.


How does the ECU measure angular velocity? Crank sensor?
That would really complicate the ECU's program and require a much faster
processor.

--
Jim Yanik
jyanik
at
kua.net

Re: Adding an O2 sensor?
 

jim beam <spamvortex@bad.example.net> wrote in
news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:

> Matt Ion wrote:
>> John Horner wrote:
>>> Jim Yanik wrote:
>>>
>>>>
>>>> Well,the desired end result is complete combustion(a clean
>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>> happening.
>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>> feedback corrects for it.it also allows for individual cylinders'
>>>> injectors to be corrected,compensating for differing air flow thru
>>>> the cylinders.They are not necessarily all equal!)
>>>>
>>>
>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>> each cylinder and adjust them independently. At best you have one
>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>> information about individual cylinders.
>>
>> Well, I can't claim to know exactly how these systems DO work, but I
>> can hypothesize that it wouldn't be all that difficult for the ECU to
>> get an idea what's going on with each cylinder individually.
>
> it's already done to some extent - angular velocity for each power
> stroke is measured, so any cylinder not producing the same "oomph" as
> the others gets individually tuned.


How does the ECU measure angular velocity? Crank sensor?
That would really complicate the ECU's program and require a much faster
processor.

--
Jim Yanik
jyanik
at
kua.net

Re: Adding an O2 sensor?
 

jim beam <spamvortex@bad.example.net> wrote in
news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:

> Matt Ion wrote:
>> John Horner wrote:
>>> Jim Yanik wrote:
>>>
>>>>
>>>> Well,the desired end result is complete combustion(a clean
>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>> happening.
>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>> feedback corrects for it.it also allows for individual cylinders'
>>>> injectors to be corrected,compensating for differing air flow thru
>>>> the cylinders.They are not necessarily all equal!)
>>>>
>>>
>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>> each cylinder and adjust them independently. At best you have one
>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>> information about individual cylinders.
>>
>> Well, I can't claim to know exactly how these systems DO work, but I
>> can hypothesize that it wouldn't be all that difficult for the ECU to
>> get an idea what's going on with each cylinder individually.
>
> it's already done to some extent - angular velocity for each power
> stroke is measured, so any cylinder not producing the same "oomph" as
> the others gets individually tuned.


How does the ECU measure angular velocity? Crank sensor?
That would really complicate the ECU's program and require a much faster
processor.

--
Jim Yanik
jyanik
at
kua.net

Re: Adding an O2 sensor?
 

Jim Yanik wrote:
> jim beam <spamvortex@bad.example.net> wrote in
> news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:
>
>> Matt Ion wrote:
>>> John Horner wrote:
>>>> Jim Yanik wrote:
>>>>
>>>>> Well,the desired end result is complete combustion(a clean
>>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>>> happening.
>>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>>> feedback corrects for it.it also allows for individual cylinders'
>>>>> injectors to be corrected,compensating for differing air flow thru
>>>>> the cylinders.They are not necessarily all equal!)
>>>>>
>>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>>> each cylinder and adjust them independently. At best you have one
>>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>>> information about individual cylinders.
>>> Well, I can't claim to know exactly how these systems DO work, but I
>>> can hypothesize that it wouldn't be all that difficult for the ECU to
>>> get an idea what's going on with each cylinder individually.
>> it's already done to some extent - angular velocity for each power
>> stroke is measured, so any cylinder not producing the same "oomph" as
>> the others gets individually tuned.
>
>
> How does the ECU measure angular velocity? Crank sensor?

yes - that sawtooth thing.

> That would really complicate the ECU's program and require a much faster
> processor.
>

check - and that's what we have! there's a lot of computing power out
there. this stuff is small beer compared to what's in the average pc.

Re: Adding an O2 sensor?
 

Jim Yanik wrote:
> jim beam <spamvortex@bad.example.net> wrote in
> news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:
>
>> Matt Ion wrote:
>>> John Horner wrote:
>>>> Jim Yanik wrote:
>>>>
>>>>> Well,the desired end result is complete combustion(a clean
>>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>>> happening.
>>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>>> feedback corrects for it.it also allows for individual cylinders'
>>>>> injectors to be corrected,compensating for differing air flow thru
>>>>> the cylinders.They are not necessarily all equal!)
>>>>>
>>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>>> each cylinder and adjust them independently. At best you have one
>>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>>> information about individual cylinders.
>>> Well, I can't claim to know exactly how these systems DO work, but I
>>> can hypothesize that it wouldn't be all that difficult for the ECU to
>>> get an idea what's going on with each cylinder individually.
>> it's already done to some extent - angular velocity for each power
>> stroke is measured, so any cylinder not producing the same "oomph" as
>> the others gets individually tuned.
>
>
> How does the ECU measure angular velocity? Crank sensor?

yes - that sawtooth thing.

> That would really complicate the ECU's program and require a much faster
> processor.
>

check - and that's what we have! there's a lot of computing power out
there. this stuff is small beer compared to what's in the average pc.

Re: Adding an O2 sensor?
 

Jim Yanik wrote:
> jim beam <spamvortex@bad.example.net> wrote in
> news:mIGdnQ8s88KDb5XYnZ2dnUVZ_vudnZ2d@speakeasy.ne t:
>
>> Matt Ion wrote:
>>> John Horner wrote:
>>>> Jim Yanik wrote:
>>>>
>>>>> Well,the desired end result is complete combustion(a clean
>>>>> exhaust),and exhaust O2 content is an indication of how well that's
>>>>> happening.
>>>>> They are real-time corrections,and measure ACTUAL exhaust output.
>>>>> (if a plug misfires,or a input-condition sensor is inaccurate,this
>>>>> feedback corrects for it.it also allows for individual cylinders'
>>>>> injectors to be corrected,compensating for differing air flow thru
>>>>> the cylinders.They are not necessarily all equal!)
>>>>>
>>>> Uh, hold on there. Few if any modern fuel injection systems monitor
>>>> each cylinder and adjust them independently. At best you have one
>>>> O2 sensor per bank on a multi-head engine. The ECU has no
>>>> information about individual cylinders.
>>> Well, I can't claim to know exactly how these systems DO work, but I
>>> can hypothesize that it wouldn't be all that difficult for the ECU to
>>> get an idea what's going on with each cylinder individually.
>> it's already done to some extent - angular velocity for each power
>> stroke is measured, so any cylinder not producing the same "oomph" as
>> the others gets individually tuned.
>
>
> How does the ECU measure angular velocity? Crank sensor?

yes - that sawtooth thing.

> That would really complicate the ECU's program and require a much faster
> processor.
>

check - and that's what we have! there's a lot of computing power out
there. this stuff is small beer compared to what's in the average pc.

Re: Adding an O2 sensor?
 

Matt Ion wrote:

>
> Well, I can't claim to know exactly how these systems DO work, but I can
> hypothesize that it wouldn't be all that difficult for the ECU to get an
> idea what's going on with each cylinder individually. Given timing
> input, it will know which cylinder is firing when, and a subsequent
> change in the O2 sensor reading is pretty easy to correlate to that
> cylinder.
>

The sensor reaction time is nowhere nearly fast enough to do what you
suggest.

John

Re: Adding an O2 sensor?
 

Matt Ion wrote:

>
> Well, I can't claim to know exactly how these systems DO work, but I can
> hypothesize that it wouldn't be all that difficult for the ECU to get an
> idea what's going on with each cylinder individually. Given timing
> input, it will know which cylinder is firing when, and a subsequent
> change in the O2 sensor reading is pretty easy to correlate to that
> cylinder.
>

The sensor reaction time is nowhere nearly fast enough to do what you
suggest.

John

Re: Adding an O2 sensor?
 

Matt Ion wrote:

>
> Well, I can't claim to know exactly how these systems DO work, but I can
> hypothesize that it wouldn't be all that difficult for the ECU to get an
> idea what's going on with each cylinder individually. Given timing
> input, it will know which cylinder is firing when, and a subsequent
> change in the O2 sensor reading is pretty easy to correlate to that
> cylinder.
>

The sensor reaction time is nowhere nearly fast enough to do what you
suggest.

John

Re: Adding an O2 sensor?
 

"John Horner" <jthorner@yahoo.com> wrote
> Matt Ion wrote:
>
>>
>> Well, I can't claim to know exactly how these systems DO
>> work, but I can hypothesize that it wouldn't be all that
>> difficult for the ECU to get an idea what's going on with
>> each cylinder individually. Given timing input, it will
>> know which cylinder is firing when, and a subsequent
>> change in the O2 sensor reading is pretty easy to
>> correlate to that cylinder.
>>
>
> The sensor reaction time is nowhere nearly fast enough to
> do what you suggest.

Tegger commented not long ago on certain Fords having one
oxygen sensor per cylinder. I googled and found support for
this.

Seems perfectly reasonable to me, timing-wise that the ECU
and O2 sensor could calibrate fuel going to each cylinder.

Re: Adding an O2 sensor?
 

"John Horner" <jthorner@yahoo.com> wrote
> Matt Ion wrote:
>
>>
>> Well, I can't claim to know exactly how these systems DO
>> work, but I can hypothesize that it wouldn't be all that
>> difficult for the ECU to get an idea what's going on with
>> each cylinder individually. Given timing input, it will
>> know which cylinder is firing when, and a subsequent
>> change in the O2 sensor reading is pretty easy to
>> correlate to that cylinder.
>>
>
> The sensor reaction time is nowhere nearly fast enough to
> do what you suggest.

Tegger commented not long ago on certain Fords having one
oxygen sensor per cylinder. I googled and found support for
this.

Seems perfectly reasonable to me, timing-wise that the ECU
and O2 sensor could calibrate fuel going to each cylinder.

Re: Adding an O2 sensor?
 

"John Horner" <jthorner@yahoo.com> wrote
> Matt Ion wrote:
>
>>
>> Well, I can't claim to know exactly how these systems DO
>> work, but I can hypothesize that it wouldn't be all that
>> difficult for the ECU to get an idea what's going on with
>> each cylinder individually. Given timing input, it will
>> know which cylinder is firing when, and a subsequent
>> change in the O2 sensor reading is pretty easy to
>> correlate to that cylinder.
>>
>
> The sensor reaction time is nowhere nearly fast enough to
> do what you suggest.

Tegger commented not long ago on certain Fords having one
oxygen sensor per cylinder. I googled and found support for
this.

Seems perfectly reasonable to me, timing-wise that the ECU
and O2 sensor could calibrate fuel going to each cylinder.