jim beam > wrote in
:

> Jim Yanik wrote:
>> jim beam > wrote in news_-dnS91tZMHfzHfRVn-
>> :
>>
>>
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/