Idle question
Thread Starter
Drifting
Joined: Dec 2012
Posts: 1,504
Likes: 73
From: Georgetown TX
Idle question
I tried posting this question on other tuner sites, but can’t seem to make it work, so I thought I would ask here
At idle, can the rpm keep surging if the engine is running too lean? No vacuum leaks found.
1989 stock, automatic, 52000 miles
At idle, can the rpm keep surging if the engine is running too lean? No vacuum leaks found.
1989 stock, automatic, 52000 miles
Last edited by mlm0; May 1, 2018 at 09:27 PM.
Team Owner
Joined: Jul 2004
Posts: 28,376
Likes: 3,260
From: Hartford WI
Did you check with the ECM as to whether it is compensating in any way? What is the IAC count when warm with everything but the motor off? If it is higher than 20-30 counts, you are not having enough air. If it is a 0 counts, you are having too much air because the throttle blades are too open or you DO have an air leak, assuming timing, fuel pressure, etc is right.
Team Owner
Joined: Jul 2004
Posts: 28,376
Likes: 3,260
From: Hartford WI
Assuming timing and fun are right and the engine is at stable operating temperature and nothing but the motor running you need to open up the throttle plate more. Turn the adjustment screw in, Rev and recheck Don't shut it off. Keep going till the count is about 20 to 30
Thread Starter
Drifting
Joined: Dec 2012
Posts: 1,504
Likes: 73
From: Georgetown TX
I know you are correct in what you are telling me, but for my knowledge, why does it matter if the iac is at 50 Seems like it has room on both side of count to work. Like I said, just got my knowledge
Team Owner
Joined: Jul 2004
Posts: 28,376
Likes: 3,260
From: Hartford WI
At 0, if it need to lessen the amount of air coming in, it cannot. Thing is we have been warned not to remove the IAC and turn the car on because it will extend past the point of no return and screw up the IAC Makes me think it will extend the pintle will extend to 0 on startup
If you set it at 50 instead of 20,i think it will take longer to reach 50 than 20.
Instructor
Joined: Sep 2007
Posts: 127
Likes: 13
From: Apollo Beach. Fla
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Supporting Vendor
Joined: Oct 2004
Posts: 761
Likes: 67