96 Ws6 Stumbles At Idle While In Gear
Thread Starter
Registered User
Joined: May 2005
Posts: 43
96 Ws6 Stumbles At Idle While In Gear
So heres the deal: I have a 1996 Trans Am Ws6 which I just bought a week ago, which is one of the cars I have always wanted! Its been awesome the past week, and still has a boat-load of power and seems to have been well taken care of its 74000 miles. However, today while I was cruising around it began to develop a slight stumble every once in a while at idle, but ONLY when in gear. (Not P or N, its fine in those) Its not enough to kill the engine but is very noticeable when it happens. (rpms fluctuate 400-900) Once you give it some gas it goes right away so I'm assuming its something like my throttle body needing cleaning?? Hopefully some of the Fbody guys can give me their thoughts on this so I can get her running smooth again.
Registered User
Joined: Jul 2001
Posts: 603
From: I-L-L-I-N-O-I-S
Re: 96 Ws6 Stumbles At Idle While In Gear
Your car is an A4, correct?
Well let me tell ya...When I bought my '95 Z28 w/ about 109,000 on the clock last fall it was acting exactly as you described with yours. A warm idle while in gear (sitting at a light for example) would stumble sometimes. Idle would be normal (550 factory setting), then out of nowhere it would just drop to about 400ish for a second or so and jump back up to the correct idle speed. Never died, but felt like it wanted to, LOL. Once you gave it some gas and got it moving it was all good.
Turned out to be the IAC (Idle Air Control) valve. Had a really low count right at 0. There was a small vacuum leak. Got that fixed and had the throttle body cleaned as well. Idle has now been perfectly solid since then (knock on wood).
Check that out first though (don't just assume it's the opti like so many do). Now if you're having consistent misses in the rpm band while cruising or at full throttle, then I'd look hard at the opti, plugs & wires, coil, ICM, etc.
Good luck,
Mike
Well let me tell ya...When I bought my '95 Z28 w/ about 109,000 on the clock last fall it was acting exactly as you described with yours. A warm idle while in gear (sitting at a light for example) would stumble sometimes. Idle would be normal (550 factory setting), then out of nowhere it would just drop to about 400ish for a second or so and jump back up to the correct idle speed. Never died, but felt like it wanted to, LOL. Once you gave it some gas and got it moving it was all good.
Turned out to be the IAC (Idle Air Control) valve. Had a really low count right at 0. There was a small vacuum leak. Got that fixed and had the throttle body cleaned as well. Idle has now been perfectly solid since then (knock on wood).
Check that out first though (don't just assume it's the opti like so many do). Now if you're having consistent misses in the rpm band while cruising or at full throttle, then I'd look hard at the opti, plugs & wires, coil, ICM, etc.
Good luck,
Mike
Registered User
Joined: Mar 2005
Posts: 607
From: Kzoo, MI
Re: 96 Ws6 Stumbles At Idle While In Gear
I had a problem somewhat similar to that. It turned out to be a broken vacuum hose, in my case the one that comes out of the passenger side of the throttle body. Take a look around and see what you can find. You might be able to hear it if it is a vacuum line - it would just sound like a lot of air being blown out of / sucked into a tube. Good luck.
Thread
Thread Starter
Forum
Replies
Last Post
F'n1996Z28SS
Cars For Sale
8
Aug 23, 2023 11:19 PM
dbusch22
Forced Induction
6
Oct 31, 2016 11:09 AM
ChrisFrez
CamaroZ28.Com Podcast
0
Mar 1, 2015 01:33 PM