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Re: 87 5k - Idle Stabilizer?

In response to my idle problem (it stalled easily and died when I pushed in
the clutch on my 87 CSTQ when coasting up to a stop light), Bob  Myers
<rmyers@wvit.wvnet.edu> said:

>Check for vac leaks.  This is a major cause of refusal to idle.
>First give everything the usual visual inspection.  Then, with the engine
>idsling, pull the oil dipstick.  If the engine dies, you probably do have a
>leak.  If nothing is found after the visual inspection, with the engine
>idling, spray around the various rubber parts with ether type starting fluid
>...  If there is a vac leak, the rpms will pick up when the ether is sucked
into the
>system through the leak.  This will give you a clue about where to look.

Good call! The 3-way rubber coupler that connects to the valve cover vent
had a couple of major cracks on the bottom side, but the real problem was
that the tube running from the 3-way coupler to the back of the air chamber
had a major hole in it near the entrance to the air chamber.  Given the size
of the leak, it's hard to imagine that the car ran as well as it did.
Replacing both parts cured the idle problem and significantly increased
engine performance.  Max boost, which had not exceeded 1.1 for as long as I
can remember, now goes to 1.3.  And I can now pull out the oil dipstick
without killing the engine. Thanks, Bob.

John Winkelman
(A chemist in a former life.)
John D. Winkelman
Disclaimer:  I couldn't have been going that fast, officer!