High Idling?
#1
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I took a trip to Ft. Myers yesterday and idling was around 750 RPM
Now I'm idling around 1250 RPM's with an occasional drop to 1000... please tell me its easy to fix...
1987 Auto S4
Now I'm idling around 1250 RPM's with an occasional drop to 1000... please tell me its easy to fix...
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1987 Auto S4
#3
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First, check that the cables from the quadrant allow the throttle plate to fully close. Next, look at hoses & gaskets that feed the intake for vacuum/air inleakage ( mostly under the manifold). Despite this being unmetered air, it can still increase the idle.
This could also be second .... or third: Swap out the MAF for a trial. A friends '89 had the idle vary from 1000 - 1500 rpm, and we swapped MAFs. His car idled perfectly, mine wouldn't start ....
This may not help, but you get what you pay for: send the cheque to Jenn
This could also be second .... or third: Swap out the MAF for a trial. A friends '89 had the idle vary from 1000 - 1500 rpm, and we swapped MAFs. His car idled perfectly, mine wouldn't start ....
This may not help, but you get what you pay for: send the cheque to Jenn
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#4
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Also - the IACV (Idle Stabilizer Valve). Search for other threads. Lots of ideas and plenty of good advice.
I have the exact same issue, but with the 85 I think I need to take off the intake shroud to get to it.
You will fix it so plan on registering..in fact...you should register. Ensures this board continues.
Curt
I have the exact same issue, but with the 85 I think I need to take off the intake shroud to get to it.
You will fix it so plan on registering..in fact...you should register. Ensures this board continues.
Curt
#6
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I was planning to register anyway, well I held up to my end of the deal now to find the problem.
Ill look for leaks... I hope its not the idle stablizer valve though *cringe*
Ill look for leaks... I hope its not the idle stablizer valve though *cringe*
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#9
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Believe it or not, on my '89 the idle is not adjustable. It's electronically controlled and even that system has no adjustment. I think the same applies to your '87.
Colin. 89GT
Colin. 89GT
#11
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Mine does the same thing... High idle when cold, 1200 or so.. Then drops to 750 or so when warm.. Kicker is.... if I shut the engine off and fire it up.. the idle then hunts between just about stalling and 750.. I can tell you what mine isn't.. still have not found the source.. Suspecting the LH at this point as I have tried/replaced/repaired just about everything else.
#12
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Chief,
your idle should be at 675 +/- 25 rpm i think for the S4 automatic. If you have idle hunting, it could be MAF, Idle Stabilizer or Vacuum Leak. If you just have a high Idle, it is probably a vacuum leak. Check your vacuum system, followed by MAF. Also do note that idle adjustment on the LH equiped 928 is only doable by connecting the Bosch KTS 300/1 "Hammer" or the JDS Spanner.
Sincerely,
Khaled
your idle should be at 675 +/- 25 rpm i think for the S4 automatic. If you have idle hunting, it could be MAF, Idle Stabilizer or Vacuum Leak. If you just have a high Idle, it is probably a vacuum leak. Check your vacuum system, followed by MAF. Also do note that idle adjustment on the LH equiped 928 is only doable by connecting the Bosch KTS 300/1 "Hammer" or the JDS Spanner.
Sincerely,
Khaled