Almost 100% sure this is caused by a bad gulp valve. For some reason, when
these go bad, No. 2 cylinder really suffers at idle. To prove if this is
the problem, disconnect the big hose that goes between the gulp valve and
the elbow into the manifold and plug it (a piece of wood dowel or a large
diameter bolt), also disconnect and plug the small hose that goes into the
gulp valve. Also check that the elbow is a secure fit in the manifold;
these have a habit of coming loose.
Lawrie
British Sportscar Center
----------
> From: Alan Bidgood <bidgood.alan@ssd.loral.com>
> To: mgs@autox.team.net
> Subject: Still won't idle
> Date: Tuesday, October 14, 1997 9:02 AM
>
> Hello again,
>
> I'm still trying to get my idle right, but I now feel
> it is more than that. Part of my concern is the damn
> California Smog test I have to get through.
>
> The car almost seems like it is only firing on three,
> although it seems to run fairly well at speed. When it
> is approaching idle the whole engine rocks quite badly.
> Originally I thought it was the carb, but more recently
> I pulled each plug lead off while the car was running,
> and when I pulled number two off, nothing changed. I
> thought I'd found the problem, but having changed the
> lead, all the leads, the distributor cap, the plug, still
> no change. It seems as if the spark on that cylinder is
> weaker (but I think that may be my imagination) In view of
> replacing everything how could one cylinder/spark etc. be
> different? The electronoic ignition/coil doesn't know one
> cylinder from another as far as the magnitude of the spark
> etc. The compression on cylinders 1,2 & 3 is similar with
> number 4 a bit lower, so I don't think it is that. Next I
> will try playing with the timing, but I don't understand
> what is going on?
>
> Any suggestions? before I take it somewhere,
>
> Thanks,
> Alan B.'
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