High idle
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
A high idle is almost always a vacuum leak.
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
Thread Starter
Advanced
Joined: Oct 2013
Posts: 62
Likes: 0
High idle
A high idle is almost always a vacuum leak.
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
Thread Starter
Advanced
Joined: Oct 2013
Posts: 62
Likes: 0
High idle
A high idle is almost always a vacuum leak.
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
I suggest a minimum idle adjustment:
http://forums.corvetteforum.com/1570563689-post1.html
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Which "little port" is that? Do you have a picture?
Early throttle bodies have two ports, later ones have three. The one on the bottom goes to the EGR solenoid. The later ones with the vacuum port on the passenger side go to the charcoal canister (earlier cars got the vacuum from the intake manifold at the same place as the PCV valve). There is also a filtered air supply that goes to the passenger side valve cover, which is part of the PCV system (it's called CCV for CrankCase Ventilation in the shop manuals).
Early throttle bodies have two ports, later ones have three. The one on the bottom goes to the EGR solenoid. The later ones with the vacuum port on the passenger side go to the charcoal canister (earlier cars got the vacuum from the intake manifold at the same place as the PCV valve). There is also a filtered air supply that goes to the passenger side valve cover, which is part of the PCV system (it's called CCV for CrankCase Ventilation in the shop manuals).
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
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The IAC is controlled by the ECM. It is actually a stepper motor and there is a stepper motor integrated circuit in the ECM that operates it. It only moves if the ECM tells it to move.