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High idle sort of fixed

Last night I took apart a lot of things on the intake to see what the
story was. In taking things out, I ended up breaking the coast valve (may
have been damaged already). Anyway, buttoned things back up and have a
steady idle at 27-3300 rpm. No more surging. I drove it around, and it's
extremely powerful. I guess the vacuum leak I felt beforer all this
started is gone now, but the idle problem. The inlet from the on off valve
that has been removed (I put a rubber plug in its place) now has a hose on
it that I use to allow unmetered air into the intake to reduce the idle. I
know, but can't do anything. The boost is still excellent and it idles at
1200, so I'm somewhat happy.

1. ISV good
2. throttle switches good
3. idle controller good
4. ECU good

I did go to check the timing this morning and it may be off by some
degrees. Can this cause the idle proble I've outlined? It no longer
surges, but goes up to 3300. What is the threshold of timing error before
the engine will not run or start? The highest vacuum I get is .3 bar.

How much does the coast (on/off) valve cost?

*Steve                                             Sachelle Babbar
*'87  5000CS Turbo 5spd 1.3-2.0 bar             <SBABBAR@IRIS.NYIT.EDU>
*Cockpit adjustable wastegate, AudiSport badge
*Disclaimer:"Any information contained herein is based purely on my own
*personal experience and may not necessarily reflect yours. Use caution as
*your results may vary from mine."