idle issue 91 l98
Thread Starter
Burning Brakes
Joined: Aug 2007
Posts: 917
Likes: 2
From: Charlotte NC
idle issue 91 l98
I have an idle issue I need help on, My vette starts up fine and idles fine (even when warm) but after I drive it for a bit, i will go to stop and it will idle at anywhere from 1800-2200 rpm witch makes it hard to stop. but if I put it in neutral and tap the gas it will drop down to normal. it sounds like a sticking cable but its not. no vac leaks, no codes, any ideas?
thanks
thanks
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
high idle
I had that once.
I cleaned the engine with a high pressure washer, and it did that.
turns out that the throttle position sensor wasn't sealed from the factory, and water makes it do that.
water, steam, coolant leak, air conditioning condensation, washing the car, etc.
I cleaned the engine with a high pressure washer, and it did that.
turns out that the throttle position sensor wasn't sealed from the factory, and water makes it do that.
water, steam, coolant leak, air conditioning condensation, washing the car, etc.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
It sounds like the throttle shaft bores are worn the the pot metal TB casting. The throttle plates can become misaligned, hang up, and not close the first time. If you don't want to buy a new TB, you may be able to find someone that will bush and seal yours.
RACE ON!!!
RACE ON!!!
Instructor
Joined: Apr 2006
Posts: 117
Likes: 1
From: east haven ct.
Do you still have the stock injectors 89-91 supposed to not be to good according to this site and they were right my 91 did alot of wierd stuff 5 of 8 injectors were bad had them changed car runs like it just came off the showroom floor.Had all that kind of stuff you talked about I would check your injector function.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Heel & Toe
Joined: Aug 2007
Posts: 17
Likes: 0
From: Old Tappan NJ
I had the same with my '91 with the L98 engine. Had to have all 8 replaced after learning 5 were bad. Complete tune up as well and the car runs great. Just curious...did you replace with ac delco or something else,. I used AC delco at 168.00 each !!!...I hope they improved them since production of 89-91. Thanks Kevin