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).
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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.