Re: Quad-4 (1228707 ECM) Rough Idle Problem

[Will Remaklus <remaklus@attglobal.net>]

nacelp wrote:

> They are talking about the old days of point ignitions, I beleive,
> and the problem to a large degree was just firing the charge.  In
> a production car, stock dissy, using points the successful ingition
> rate was like 92%, and with all the advancements it's up to 98+%
> nowadays.
>
> Sure the bigger the cam the lousier the idle, but I'd venture a
> guess they are really hinting at non streetable.

The application was a late model Nissan SE-R.  See

  here:http://www.se-r.net/about/200sx/scc/july97/july.html

> I'd be most suspicious of your triggering some antistall part of
> the code.  Where the ecm makes drastic changes, to prevent a
> stall at any cost.

I also tried disconnecting the EST output from the ECM such that
the ignition module controls the timing: no difference.

Last night I pulled the cams so that I can take some measurements to
verify whether or not they are a factory profile.

[This engine was an unused spare from a race team.  In addition,
 there are no partial VIN numbers or other markings that one would
 expect to see on a production engine.  As such, it is of course
 possible that the cams might be other than stock...]

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