Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik wrote:
> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
> rw@speakeasy.net:
>
>
>>r2000swler@hotmail.com wrote:
>>
>>>TeGGeR® wrote:
>>>
>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>
>>>Hopefully this is correct now.
>>>
>>>Thanks to all for their help, especially Jim Yanik.
>>>
>>>--
>>>TeGGeR®
>>>
>>>The Unofficial Honda/Acura FAQ
>>>www.tegger.com/hondafaq/
>>>--------------------------------------
>>>I think in the 1990 Honda Civic, the igniter also provides
>>>for for some PWM control. It senses the back EMF and
>>>kills the coil drive at the correct momment to insure a
>>>hot spark. I played with an ignitor and couldn't get it
>>>to because correctly until I connected to to a Honda
>>>igntion coil. As I varied the frequency of the drive pulses,
>>> all the same width, the output created wider pulse at higher
>>>"RPM".
>>>
>>>Terry
>>>
>>
>>interesting! i'd read that they did that, but just haven't had the time
>>to sit down & test for it. thanks for the confirmation!
>>
>>
>
>
> That is probably what the IC in the igniter does.(control PW.)
> The ECU merely provides the trigger at the proper time.
>
so where does it adjust pulse width - has to be on the front end, right?
if it was on the rear, the timing would be off. or maybe the ecu
already knows what the igniter's timing characteristics are and adjusts
accordingly?...

Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik wrote:
> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
> rw@speakeasy.net:
>
>
>>r2000swler@hotmail.com wrote:
>>
>>>TeGGeR® wrote:
>>>
>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>
>>>Hopefully this is correct now.
>>>
>>>Thanks to all for their help, especially Jim Yanik.
>>>
>>>--
>>>TeGGeR®
>>>
>>>The Unofficial Honda/Acura FAQ
>>>www.tegger.com/hondafaq/
>>>--------------------------------------
>>>I think in the 1990 Honda Civic, the igniter also provides
>>>for for some PWM control. It senses the back EMF and
>>>kills the coil drive at the correct momment to insure a
>>>hot spark. I played with an ignitor and couldn't get it
>>>to because correctly until I connected to to a Honda
>>>igntion coil. As I varied the frequency of the drive pulses,
>>> all the same width, the output created wider pulse at higher
>>>"RPM".
>>>
>>>Terry
>>>
>>
>>interesting! i'd read that they did that, but just haven't had the time
>>to sit down & test for it. thanks for the confirmation!
>>
>>
>
>
> That is probably what the IC in the igniter does.(control PW.)
> The ECU merely provides the trigger at the proper time.
>
so where does it adjust pulse width - has to be on the front end, right?
if it was on the rear, the timing would be off. or maybe the ecu
already knows what the igniter's timing characteristics are and adjusts
accordingly?...

Re: Unofficial FAQ: Ignition corrections
 

jim beam <nospam@example.net> wrote in
news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:

> Jim Yanik wrote:
>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>> rw@speakeasy.net:
>>
>>
>>>r2000swler@hotmail.com wrote:
>>>
>>>>TeGGeR® wrote:
>>>>
>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>
>>>>Hopefully this is correct now.
>>>>
>>>>Thanks to all for their help, especially Jim Yanik.
>>>>
>>>>--
>>>>TeGGeR®
>>>>
>>>>The Unofficial Honda/Acura FAQ
>>>>www.tegger.com/hondafaq/
>>>>--------------------------------------
>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>for for some PWM control. It senses the back EMF and
>>>>kills the coil drive at the correct momment to insure a
>>>>hot spark. I played with an ignitor and couldn't get it
>>>>to because correctly until I connected to to a Honda
>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>> all the same width, the output created wider pulse at higher
>>>>"RPM".
>>>>
>>>>Terry
>>>>
>>>
>>>interesting! i'd read that they did that, but just haven't had the
>>>time to sit down & test for it. thanks for the confirmation!
>>>
>>>
>>
>>
>> That is probably what the IC in the igniter does.(control PW.)
>> The ECU merely provides the trigger at the proper time.
>>
> so where does it adjust pulse width - has to be on the front end,
> right?
> if it was on the rear, the timing would be off. or maybe the ecu
> already knows what the igniter's timing characteristics are and
> adjusts accordingly?...
>
>


I think the ECU holds ground on Terminal 4 for the appropriate length of
time, which keeps the igniter driving the coil until ground is removed.
Once ground is removed from Pin 4, the IC switches off coil drive and the
field collapses.

The ECU decides when to apply ground and break it based on the inputs of
various sensors, such as the Crank Angle Sensor. It needs to know current
RPM, cylinder position and crank angle.

Terry is also indicating that the coil is allowed to charge for a longer
time at high RPMs to ensure a fatter spark under harsher conditions.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

jim beam <nospam@example.net> wrote in
news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:

> Jim Yanik wrote:
>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>> rw@speakeasy.net:
>>
>>
>>>r2000swler@hotmail.com wrote:
>>>
>>>>TeGGeR® wrote:
>>>>
>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>
>>>>Hopefully this is correct now.
>>>>
>>>>Thanks to all for their help, especially Jim Yanik.
>>>>
>>>>--
>>>>TeGGeR®
>>>>
>>>>The Unofficial Honda/Acura FAQ
>>>>www.tegger.com/hondafaq/
>>>>--------------------------------------
>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>for for some PWM control. It senses the back EMF and
>>>>kills the coil drive at the correct momment to insure a
>>>>hot spark. I played with an ignitor and couldn't get it
>>>>to because correctly until I connected to to a Honda
>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>> all the same width, the output created wider pulse at higher
>>>>"RPM".
>>>>
>>>>Terry
>>>>
>>>
>>>interesting! i'd read that they did that, but just haven't had the
>>>time to sit down & test for it. thanks for the confirmation!
>>>
>>>
>>
>>
>> That is probably what the IC in the igniter does.(control PW.)
>> The ECU merely provides the trigger at the proper time.
>>
> so where does it adjust pulse width - has to be on the front end,
> right?
> if it was on the rear, the timing would be off. or maybe the ecu
> already knows what the igniter's timing characteristics are and
> adjusts accordingly?...
>
>


I think the ECU holds ground on Terminal 4 for the appropriate length of
time, which keeps the igniter driving the coil until ground is removed.
Once ground is removed from Pin 4, the IC switches off coil drive and the
field collapses.

The ECU decides when to apply ground and break it based on the inputs of
various sensors, such as the Crank Angle Sensor. It needs to know current
RPM, cylinder position and crank angle.

Terry is also indicating that the coil is allowed to charge for a longer
time at high RPMs to ensure a fatter spark under harsher conditions.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

TeGGeR® wrote:
> jim beam <nospam@example.net> wrote in
> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>
>
>>Jim Yanik wrote:
>>
>>>jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>>rw@speakeasy.net:
>>>
>>>
>>>
>>>>r2000swler@hotmail.com wrote:
>>>>
>>>>
>>>>>TeGGeR® wrote:
>>>>>
>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>
>>>>>Hopefully this is correct now.
>>>>>
>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>
>>>>>--
>>>>>TeGGeR®
>>>>>
>>>>>The Unofficial Honda/Acura FAQ
>>>>>www.tegger.com/hondafaq/
>>>>>--------------------------------------
>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>for for some PWM control. It senses the back EMF and
>>>>>kills the coil drive at the correct momment to insure a
>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>to because correctly until I connected to to a Honda
>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>>all the same width, the output created wider pulse at higher
>>>>>"RPM".
>>>>>
>>>>>Terry
>>>>>
>>>>
>>>>interesting! i'd read that they did that, but just haven't had the
>>>>time to sit down & test for it. thanks for the confirmation!
>>>>
>>>>
>>>
>>>
>>>That is probably what the IC in the igniter does.(control PW.)
>>>The ECU merely provides the trigger at the proper time.
>>>
>>
>>so where does it adjust pulse width - has to be on the front end,
>>right?
>> if it was on the rear, the timing would be off. or maybe the ecu
>>already knows what the igniter's timing characteristics are and
>>adjusts accordingly?...
>>
>>
>
>
>
> I think the ECU holds ground on Terminal 4 for the appropriate length of
> time, which keeps the igniter driving the coil until ground is removed.
> Once ground is removed from Pin 4, the IC switches off coil drive and the
> field collapses.
>
> The ECU decides when to apply ground and break it based on the inputs of
> various sensors, such as the Crank Angle Sensor. It needs to know current
> RPM, cylinder position and crank angle.
>
> Terry is also indicating that the coil is allowed to charge for a longer
> time at high RPMs to ensure a fatter spark under harsher conditions.
>
yes, but that longer time seems to be determined by the igniter, not the
ecu, if i understand jim yanik correctly. it kind of has to be because
only the igniter is set up to meter the actual flyback, and that is
itself a function of the health of the system.

Re: Unofficial FAQ: Ignition corrections
 

TeGGeR® wrote:
> jim beam <nospam@example.net> wrote in
> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>
>
>>Jim Yanik wrote:
>>
>>>jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>>rw@speakeasy.net:
>>>
>>>
>>>
>>>>r2000swler@hotmail.com wrote:
>>>>
>>>>
>>>>>TeGGeR® wrote:
>>>>>
>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>
>>>>>Hopefully this is correct now.
>>>>>
>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>
>>>>>--
>>>>>TeGGeR®
>>>>>
>>>>>The Unofficial Honda/Acura FAQ
>>>>>www.tegger.com/hondafaq/
>>>>>--------------------------------------
>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>for for some PWM control. It senses the back EMF and
>>>>>kills the coil drive at the correct momment to insure a
>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>to because correctly until I connected to to a Honda
>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>>all the same width, the output created wider pulse at higher
>>>>>"RPM".
>>>>>
>>>>>Terry
>>>>>
>>>>
>>>>interesting! i'd read that they did that, but just haven't had the
>>>>time to sit down & test for it. thanks for the confirmation!
>>>>
>>>>
>>>
>>>
>>>That is probably what the IC in the igniter does.(control PW.)
>>>The ECU merely provides the trigger at the proper time.
>>>
>>
>>so where does it adjust pulse width - has to be on the front end,
>>right?
>> if it was on the rear, the timing would be off. or maybe the ecu
>>already knows what the igniter's timing characteristics are and
>>adjusts accordingly?...
>>
>>
>
>
>
> I think the ECU holds ground on Terminal 4 for the appropriate length of
> time, which keeps the igniter driving the coil until ground is removed.
> Once ground is removed from Pin 4, the IC switches off coil drive and the
> field collapses.
>
> The ECU decides when to apply ground and break it based on the inputs of
> various sensors, such as the Crank Angle Sensor. It needs to know current
> RPM, cylinder position and crank angle.
>
> Terry is also indicating that the coil is allowed to charge for a longer
> time at high RPMs to ensure a fatter spark under harsher conditions.
>
yes, but that longer time seems to be determined by the igniter, not the
ecu, if i understand jim yanik correctly. it kind of has to be because
only the igniter is set up to meter the actual flyback, and that is
itself a function of the health of the system.

Re: Unofficial FAQ: Ignition corrections
 

"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns9674E85E11CCFtegger@207.14.113.17:

> jim beam <nospam@example.net> wrote in
> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>
>> Jim Yanik wrote:
>>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>> rw@speakeasy.net:
>>>
>>>
>>>>r2000swler@hotmail.com wrote:
>>>>
>>>>>TeGGeR® wrote:
>>>>>
>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>
>>>>>Hopefully this is correct now.
>>>>>
>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>
>>>>>--
>>>>>TeGGeR®
>>>>>
>>>>>The Unofficial Honda/Acura FAQ
>>>>>www.tegger.com/hondafaq/
>>>>>--------------------------------------
>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>for for some PWM control. It senses the back EMF and
>>>>>kills the coil drive at the correct momment to insure a
>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>to because correctly until I connected to to a Honda
>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>> all the same width, the output created wider pulse at higher
>>>>>"RPM".
>>>>>
>>>>>Terry
>>>>>
>>>>
>>>>interesting! i'd read that they did that, but just haven't had the
>>>>time to sit down & test for it. thanks for the confirmation!
>>>>
>>>>
>>>
>>>
>>> That is probably what the IC in the igniter does.(control PW.)
>>> The ECU merely provides the trigger at the proper time.
>>>
>> so where does it adjust pulse width - has to be on the front end,
>> right?
>> if it was on the rear, the timing would be off. or maybe the ecu
>> already knows what the igniter's timing characteristics are and
>> adjusts accordingly?...
>>
>>
>
>
> I think the ECU holds ground on Terminal 4 for the appropriate length
> of time, which keeps the igniter driving the coil until ground is
> removed. Once ground is removed from Pin 4, the IC switches off coil
> drive and the field collapses.

I do not believe this,as the IC inside the igniter monitors coil current.
>
> The ECU decides when to apply ground and break it based on the inputs
> of various sensors, such as the Crank Angle Sensor. It needs to know
> current RPM, cylinder position and crank angle.
>
> Terry is also indicating that the coil is allowed to charge for a
> longer time at high RPMs to ensure a fatter spark under harsher
> conditions.
>

Yes,coil current has to reach some preset point before the IC shuts off the
Darlington. That's the job of that IC.

The only way we will truly know for sure is to get a look at the IC's app
sheet,or scope the ECU signal to the igniter and see if it's pulse width
increases.If it does,then it controls the PW,not the IC.

--
Jim Yanik
jyanik
at
kua.net

Re: Unofficial FAQ: Ignition corrections
 

"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns9674E85E11CCFtegger@207.14.113.17:

> jim beam <nospam@example.net> wrote in
> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>
>> Jim Yanik wrote:
>>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>> rw@speakeasy.net:
>>>
>>>
>>>>r2000swler@hotmail.com wrote:
>>>>
>>>>>TeGGeR® wrote:
>>>>>
>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>
>>>>>Hopefully this is correct now.
>>>>>
>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>
>>>>>--
>>>>>TeGGeR®
>>>>>
>>>>>The Unofficial Honda/Acura FAQ
>>>>>www.tegger.com/hondafaq/
>>>>>--------------------------------------
>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>for for some PWM control. It senses the back EMF and
>>>>>kills the coil drive at the correct momment to insure a
>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>to because correctly until I connected to to a Honda
>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>> all the same width, the output created wider pulse at higher
>>>>>"RPM".
>>>>>
>>>>>Terry
>>>>>
>>>>
>>>>interesting! i'd read that they did that, but just haven't had the
>>>>time to sit down & test for it. thanks for the confirmation!
>>>>
>>>>
>>>
>>>
>>> That is probably what the IC in the igniter does.(control PW.)
>>> The ECU merely provides the trigger at the proper time.
>>>
>> so where does it adjust pulse width - has to be on the front end,
>> right?
>> if it was on the rear, the timing would be off. or maybe the ecu
>> already knows what the igniter's timing characteristics are and
>> adjusts accordingly?...
>>
>>
>
>
> I think the ECU holds ground on Terminal 4 for the appropriate length
> of time, which keeps the igniter driving the coil until ground is
> removed. Once ground is removed from Pin 4, the IC switches off coil
> drive and the field collapses.

I do not believe this,as the IC inside the igniter monitors coil current.
>
> The ECU decides when to apply ground and break it based on the inputs
> of various sensors, such as the Crank Angle Sensor. It needs to know
> current RPM, cylinder position and crank angle.
>
> Terry is also indicating that the coil is allowed to charge for a
> longer time at high RPMs to ensure a fatter spark under harsher
> conditions.
>

Yes,coil current has to reach some preset point before the IC shuts off the
Darlington. That's the job of that IC.

The only way we will truly know for sure is to get a look at the IC's app
sheet,or scope the ECU signal to the igniter and see if it's pulse width
increases.If it does,then it controls the PW,not the IC.

--
Jim Yanik
jyanik
at
kua.net

Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik <jyanik@abuse.gov.> wrote in
news:Xns96755E000744Ejyanikkuanet@129.250.170.84:

> "TeGGeR®" <tegger@tegger.c0m> wrote in
> news:Xns9674E85E11CCFtegger@207.14.113.17:
>
>> jim beam <nospam@example.net> wrote in
>> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>>
>>> Jim Yanik wrote:
>>>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>>> rw@speakeasy.net:
>>>>
>>>>
>>>>>r2000swler@hotmail.com wrote:
>>>>>
>>>>>>TeGGeR® wrote:
>>>>>>
>>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>>
>>>>>>Hopefully this is correct now.
>>>>>>
>>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>>
>>>>>>--
>>>>>>TeGGeR®
>>>>>>
>>>>>>The Unofficial Honda/Acura FAQ
>>>>>>www.tegger.com/hondafaq/
>>>>>>--------------------------------------
>>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>>for for some PWM control. It senses the back EMF and
>>>>>>kills the coil drive at the correct momment to insure a
>>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>>to because correctly until I connected to to a Honda
>>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>>> all the same width, the output created wider pulse at higher
>>>>>>"RPM".
>>>>>>
>>>>>>Terry
>>>>>>
>>>>>
>>>>>interesting! i'd read that they did that, but just haven't had the
>>>>>time to sit down & test for it. thanks for the confirmation!
>>>>>
>>>>>
>>>>
>>>>
>>>> That is probably what the IC in the igniter does.(control PW.)
>>>> The ECU merely provides the trigger at the proper time.
>>>>
>>> so where does it adjust pulse width - has to be on the front end,
>>> right?
>>> if it was on the rear, the timing would be off. or maybe the ecu
>>> already knows what the igniter's timing characteristics are and
>>> adjusts accordingly?...
>>>
>>>
>>
>>
>> I think the ECU holds ground on Terminal 4 for the appropriate length
>> of time, which keeps the igniter driving the coil until ground is
>> removed. Once ground is removed from Pin 4, the IC switches off coil
>> drive and the field collapses.
>
> I do not believe this,as the IC inside the igniter monitors coil
> current.


So I've read.



>>
>> The ECU decides when to apply ground and break it based on the inputs
>> of various sensors, such as the Crank Angle Sensor. It needs to know
>> current RPM, cylinder position and crank angle.
>>
>> Terry is also indicating that the coil is allowed to charge for a
>> longer time at high RPMs to ensure a fatter spark under harsher
>> conditions.
>>
>
> Yes,coil current has to reach some preset point before the IC shuts
> off the Darlington. That's the job of that IC.
>
> The only way we will truly know for sure is to get a look at the IC's
> app sheet,or scope the ECU signal to the igniter and see if it's pulse
> width increases.If it does,then it controls the PW,not the IC.
>


Terry seems to have determined that there is evidence of this.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik <jyanik@abuse.gov.> wrote in
news:Xns96755E000744Ejyanikkuanet@129.250.170.84:

> "TeGGeR®" <tegger@tegger.c0m> wrote in
> news:Xns9674E85E11CCFtegger@207.14.113.17:
>
>> jim beam <nospam@example.net> wrote in
>> news:U4KdnVF_erM53DPfRVn-jw@speakeasy.net:
>>
>>> Jim Yanik wrote:
>>>> jim beam <nospam@example.net> wrote in news:o_-dnS91tZMHfzHfRVn-
>>>> rw@speakeasy.net:
>>>>
>>>>
>>>>>r2000swler@hotmail.com wrote:
>>>>>
>>>>>>TeGGeR® wrote:
>>>>>>
>>>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>>>
>>>>>>Hopefully this is correct now.
>>>>>>
>>>>>>Thanks to all for their help, especially Jim Yanik.
>>>>>>
>>>>>>--
>>>>>>TeGGeR®
>>>>>>
>>>>>>The Unofficial Honda/Acura FAQ
>>>>>>www.tegger.com/hondafaq/
>>>>>>--------------------------------------
>>>>>>I think in the 1990 Honda Civic, the igniter also provides
>>>>>>for for some PWM control. It senses the back EMF and
>>>>>>kills the coil drive at the correct momment to insure a
>>>>>>hot spark. I played with an ignitor and couldn't get it
>>>>>>to because correctly until I connected to to a Honda
>>>>>>igntion coil. As I varied the frequency of the drive pulses,
>>>>>> all the same width, the output created wider pulse at higher
>>>>>>"RPM".
>>>>>>
>>>>>>Terry
>>>>>>
>>>>>
>>>>>interesting! i'd read that they did that, but just haven't had the
>>>>>time to sit down & test for it. thanks for the confirmation!
>>>>>
>>>>>
>>>>
>>>>
>>>> That is probably what the IC in the igniter does.(control PW.)
>>>> The ECU merely provides the trigger at the proper time.
>>>>
>>> so where does it adjust pulse width - has to be on the front end,
>>> right?
>>> if it was on the rear, the timing would be off. or maybe the ecu
>>> already knows what the igniter's timing characteristics are and
>>> adjusts accordingly?...
>>>
>>>
>>
>>
>> I think the ECU holds ground on Terminal 4 for the appropriate length
>> of time, which keeps the igniter driving the coil until ground is
>> removed. Once ground is removed from Pin 4, the IC switches off coil
>> drive and the field collapses.
>
> I do not believe this,as the IC inside the igniter monitors coil
> current.


So I've read.



>>
>> The ECU decides when to apply ground and break it based on the inputs
>> of various sensors, such as the Crank Angle Sensor. It needs to know
>> current RPM, cylinder position and crank angle.
>>
>> Terry is also indicating that the coil is allowed to charge for a
>> longer time at high RPMs to ensure a fatter spark under harsher
>> conditions.
>>
>
> Yes,coil current has to reach some preset point before the IC shuts
> off the Darlington. That's the job of that IC.
>
> The only way we will truly know for sure is to get a look at the IC's
> app sheet,or scope the ECU signal to the igniter and see if it's pulse
> width increases.If it does,then it controls the PW,not the IC.
>


Terry seems to have determined that there is evidence of this.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

One more update:
http://www.tegger.com/hondafaq/ignit...ion/index.html

This has been a most interesting thread, I must say.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

One more update:
http://www.tegger.com/hondafaq/ignit...ion/index.html

This has been a most interesting thread, I must say.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik wrote (in part):

Yes,coil current has to reach some preset point before the IC shuts off
the
Darlington. That's the job of that IC.

The only way we will truly know for sure is to get a look at the IC's
app
sheet,or scope the ECU signal to the igniter and see if it's pulse
width
increases.If it does,then it controls the PW,not the IC.

--
Jim Yanik
---------------------------

I have several "systems" pulled from cars to be crushed.
I rigged a 1990 ECM and sensors, with igniter to try
and figure out what was going on.

I am after a simple way to monitor the on time of the FIs.

I was kind of suprised to see the ignition pulse width
incrase with engine speed. I used a dual channel oscilloscope
and the output from the ECM stayed the same.

I experimented using a HP pulse generator to drive the igniter
by itself and found the same thing to be true. In my celica the PW
is directly controled by the ECM. I am asuming the IC monitors the
delta V, or rate of change and integrates the data to determine PW.

I will try to test my 1991 Civc this weekend. I have brought most of
the
ECM outputs and inputs via 1K isolation resistors to a breakout box
for testing.

I think it will be very usefull to measure on ratio of the FIs to
squeeze
every erg from the fuel for best MGP.

I can say that in many ways the ECM doesn't work the way I thought.
There are odd actions during the warm up period.

One important point is that it looks like Honda skimps on teh heat sink
compound. Of course the engine runs hotter then the igniter, so I am
not at all sure that adding more thermal coupling will help. I have
thought
of adding a "heat pipe" tp remove heat from the igniter. I now consider
the
igniter a subsystem that is doomed to failure. It simply operates too
hot
for prolonged life.

Having said that, a friend's 1990 Civic has ~200K and is still on the
original igniter. Somewhere I have a motorola "designing for long
life of Si devices"(something like that) that says that for every 3
degree
rise in temp over 20C, the life will be cut in half. But based on that
the
~90 degrees C engine temp the igniter ought to fail in the first 100
miles.
There are many things I just don't understand here.

But I now carry a spare ECM and igniter "just in case".

Terry

Re: Unofficial FAQ: Ignition corrections
 

Jim Yanik wrote (in part):

Yes,coil current has to reach some preset point before the IC shuts off
the
Darlington. That's the job of that IC.

The only way we will truly know for sure is to get a look at the IC's
app
sheet,or scope the ECU signal to the igniter and see if it's pulse
width
increases.If it does,then it controls the PW,not the IC.

--
Jim Yanik
---------------------------

I have several "systems" pulled from cars to be crushed.
I rigged a 1990 ECM and sensors, with igniter to try
and figure out what was going on.

I am after a simple way to monitor the on time of the FIs.

I was kind of suprised to see the ignition pulse width
incrase with engine speed. I used a dual channel oscilloscope
and the output from the ECM stayed the same.

I experimented using a HP pulse generator to drive the igniter
by itself and found the same thing to be true. In my celica the PW
is directly controled by the ECM. I am asuming the IC monitors the
delta V, or rate of change and integrates the data to determine PW.

I will try to test my 1991 Civc this weekend. I have brought most of
the
ECM outputs and inputs via 1K isolation resistors to a breakout box
for testing.

I think it will be very usefull to measure on ratio of the FIs to
squeeze
every erg from the fuel for best MGP.

I can say that in many ways the ECM doesn't work the way I thought.
There are odd actions during the warm up period.

One important point is that it looks like Honda skimps on teh heat sink
compound. Of course the engine runs hotter then the igniter, so I am
not at all sure that adding more thermal coupling will help. I have
thought
of adding a "heat pipe" tp remove heat from the igniter. I now consider
the
igniter a subsystem that is doomed to failure. It simply operates too
hot
for prolonged life.

Having said that, a friend's 1990 Civic has ~200K and is still on the
original igniter. Somewhere I have a motorola "designing for long
life of Si devices"(something like that) that says that for every 3
degree
rise in temp over 20C, the life will be cut in half. But based on that
the
~90 degrees C engine temp the igniter ought to fail in the first 100
miles.
There are many things I just don't understand here.

But I now carry a spare ECM and igniter "just in case".

Terry

Re: Unofficial FAQ: Ignition corrections
 

r2000swler@hotmail.com wrote in
news:1118859696.926058.152280@z14g2000cwz.googlegr oups.com:

> I now consider the igniter a subsystem that is doomed to failure. It
> simply operates too hot for prolonged life.
>
> Having said that, a friend's 1990 Civic has ~200K and is still on the
> original igniter.



My '91 Integra has 248K miles and the interior of the distributor is
entirely original, except for the rotor which I change every few years.


I wonder if maintenance might be a factor in igniter longevity the way it
is with coil longevity. Since the igniter is doing a lot of monitoring as
well as current carrying, might a large enough deviation from design spec
in ignition system characteristics overload the igniter?



--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/