re. i87 5kt intermittent no start

[Ben Swann]

How did you check the throttle body switch?  Did you actually verify operation – that
the switch makes and breaks contact by using a test connector?  Did you verify there are
no broken wires off the switch?  Did you run connectivity test from the ECU connector
through the switch?

More:  what happens when you disconnect the ISV connector – does the idle drop?

What happens when you pinch the air line into the ISV – does this alter the idle?

I have found in general, the idle switch adjust is about 3 full turns out  (MC-1/MAC-11)
to produce proper idle.  This is when CO is adjusted properly and no – I repeat NO
airleaks.  YMMV.

You provide a lot of info here, but no complete description of the problem.  If you just
got the car, assume a lot of sorting is in order and you will find leaks.  OK – get back
on that to see if this leads to a proper diagnosis.

Ben


[Date: Tue, 13 May 2008 19:17:37 -0400
From: Dave Yentema <yentemad at rider.edu>
Subject: i87 5kt intermittent no start
To: quattro at audifans.com
Message-ID: <000e01c8b54f$8873e680$fb6e4b0a at DEATH>
Content-Type: text/plain;	charset="iso-8859-1"

Figures that when i finally get all of the right parts installed, my car doesn't want to
run right. I took that plastic plug out that i had filling the hole for the idle screw,
and installed the right one. Screwed it in until i heard the throttle switch click, then
backed it off by about a half a turn. Car starts right up and runs like a champ, a
little too high rpm, but was running very well. Shut it off, played with a few things
like the isv, the throttle switch, etc and went to start the car again. It fired once
but didn't catch and then didnt fire again until i turned the key off and back on again
but still didn't catch. Went back out and played with some more things, took the MM hose
off, cleaned the gunk off of the butterfly valve, backed the screw off a bit, etc. Tried
it again, no luck. Tried one more time, but this time i punched the gas right as it
fired and it caught and i held it at about 1500 for a bit and let off. It stumbled
around for a bit but eventually started  idling beautifully. On a quick test drive it
ran amazing as well. Shut it off and went to start again, and its doing it again... I
used this as an excuse to get some new spark plugs (NGK bp6et)and it runs a lot
smoother, but still has this problem..

Any ideas?


-Dave]