ECM fault? Marginally GMECM

[Akselrud, Boris]

Out of limits of smooth idle. it fluctuates about 50..80 RPM, at the lower
end it is shaking all body and at the upper it is smooth.

There is no info - all parameters are within limits according to service
manual, no error codes.

-----Original Message-----
From: David Cooley [mailto:n5xmt at bellsouth.net]
Sent: Wednesday, November 10, 1999 11:56 AM
To: gmecm at efi332.eng.ohio-state.edu
Subject: RE: ECM fault? Marginally GMECM


At 11:39 AM 11/10/1999 -0500, you wrote:
>I understand that there is constant need for ECM to support 14.7.:1 AFR and
>all by itself it is not stable and requires a continuous feedback to
>support.
>But it appears that ECM over/under compensating and this is what is pushing
>idle in and out of the limits.

What limits, Your limits?  If the idle exceeded the "limits" programmed 
into the ECM, you'd set a code and have the check engine light on.  You 
still have never stated how many RPM the engine idle varies.  No requests 
for info have been answered yet, and there is no way to troubleshoot the 
problem without data.
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David Cooley N5XMT Internet: N5XMT at bellsouth.net
Packet: N5XMT at KQ4LO.#INT.NC.USA.NA T.A.P.R. Member #7068
We are Borg... Prepare to be assimilated!
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