No Subject

[walter@quattro.corp.inmet.com (Walter Meares)]

> > 
> > On a different note...my 90 200T has developed a strange symptom.
> > After it has  sat for several hours, occasionally it will not idle.
> > I can keep it running by pressing on the accelerator lightly
> > but when I remove it, the engine rpm are too low to keep
> > it running.  If I would tap on the idle stabilization valve
> > then all would be OK.  Has anyone had any experience in 
> > cleaning or repairing these critters?  My 200 also seems
> > a bit hard to start cold.  It takes about 4 seconds on the
> > starter for it to fire.  Any suggestions on where to start?
> > It has been that way since I bought the car 1 year ago.
> > 
> > Thanks
> > rich
> > 

[...] 

> As far as the idle stabilizer goes, I know other people 
> have had success with taking it off and cleaning it out
> with WD40,  although I'd use carburetor cleaner....IMHO
> 
> 
> Mike L.


I just replaced the charming little idle stabilizer valve on my 4000SQ.  
Similar symptoms to your problem, erratic idle, except in my case it would
stick fast, about 1200 rpm.  Before I bought a new valve I opened up the old
one (guess I was feeling gutsy that day).  Inside it looks like a little 
motor armature with brushes and contacts.  On mine the brushes were worn and
burned and the contacts were severely pitted, burned and gouged.  I cleaned
it up with emory paper, reassembled it, and the car idled fine again! Mine
had only about 80K miles on it.  I diagnosed it by checking the duty cycle
reading, it was always "pegged" trying to drive the valve, but could be fixed
by tapping on the valve.

But I knew the clean-up repair wouldn't last, so I bought a new one.  I
bought locally, it ran around $190.

If its just gunked up inside (in the air passage) you might be able to clean
it.  Another problem I noticed while replacing it is that the aging rubber
plenum where the valve attaches no longer seals real well around the nipples
on the valve; I used plastic tie wraps to make it seal more tightly because 
that's what I had around, but hose clamps would probably work even better.  Air
leaks here are bad news and can affect idle and overall performance.

Walter

--
Walter Meares		Intermetrics, Inc.	walter@inmet.inmet.com
Information Systems	733 Concord Ave		Cambridge MA 02138
(617) 661-1840