Idle wont drop
Thread Starter
Racer
Joined: Jan 2010
Posts: 347
Likes: 12
From: Deltona FL
Idle wont drop
When I come to a stop the idle wont drop it stays at 1k and then drops only when I tap the gas pedal. So that leads me to believe it is mechanical, Throttle cable does not look to be in the best shape or is it the TB? 86 l98
Drifting
Joined: Sep 2004
Posts: 1,961
Likes: 2
From: Fort Knox
actually sounds electromechanical. Try cleaning the IAC, actuallly you could just take off your throtle body and clean the whole thing. Which is not a bad idea for a 24 year old car if you've never done so.
Thread Starter
Racer
Joined: Jan 2010
Posts: 347
Likes: 12
From: Deltona FL
I took off the TB last week and cleaned it and all new gaskets, Cleaned IAC and housing
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
It could be the shaft on the TB is worn and is sticking and binding, this has happened to many because of the years of use. You can get it drilled out and have bushings installed or get a new or used TB..WW
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
It's the Throttle body. take the cable off, and move it by hand. you will see what you are talking about translates into something you can see, feel and repair.
Pro
Joined: Mar 1999
Posts: 678
Likes: 0
From: Oslo, Norway
If it is somethi mechanical its easy to detect. First feel by moving the butterflies by hand if something sticks. If it feels smooth press the throttle pedal down and rise it slowly til it stops. Go out and se on the throttlebody it it is possible to press the butterflies more in to position. If so there is a mechanical problem. Either the bearing in the pedal, bad hose or bad bearings in the throttle body. You can wiggle the shaft in the throttlebody and see if there is some room if so the throttle body is worn and false air can come in to the engine without the MAF sensing it .
It might also be false air in other places as vacuum hoses, air leakage between runners and manifold or between runners and plenum.
False air you can detect by sprying start gas or propane around places where there may be a suspicion. If the rpm rises slightly there is a leakage there.
It might also be false air in other places as vacuum hoses, air leakage between runners and manifold or between runners and plenum.
False air you can detect by sprying start gas or propane around places where there may be a suspicion. If the rpm rises slightly there is a leakage there.
