High idle
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
It says it idles to 1200 when cold and 200 when warm? I don't think so. I don't believe the engine can sustain itself at 200. If that is what you are reading, maybe something is wrong with the tach and you should check what the ECM thinks.
Team Owner
Joined: Feb 2003
Posts: 54,121
Likes: 9,436
From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
2015 C2 of Year Finalist
find a shop that is willing to plug it into a scan tool and read the pentameters of each sensor and see what one is out of wack
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Le Mans Master
Joined: Sep 2009
Posts: 6,341
Likes: 1,148
From: Vermilion OH
Have you noticed a drop in fuel mileage? Have you checked the engine over for any vacuum leaks? Have you cleaned the throttle body thoroughly? Those would be the first steps I would take.
Thread Starter
5th Gear
Joined: Mar 2018
Posts: 5
Likes: 0
Hgh idle
I tried cleaning throttle body ...no luck I'm concerned because engine seems to be running a little hot 215 to 225'f next step take it to shop to see if they can isolate problem thanks for all your suggestions!
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Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
What is the ambien temperature? What are you doing when you get it that high? Sitting in idle or what?
Often they have a "specialist" for that sort of job. IOW, some guy who drew the short straw and has to deal with old stuff nobody wants to work with. Sooner or later, you need a scanner to see things. Might as well buy one.
Race Director
Joined: Oct 2012
Posts: 17,388
Likes: 6,530
From: Melbourne, FL
Sounds like you've got a vacuum leak. There's only a few vacuum lines, check to make sure they'e all plugged in. That's normal operating temperatures for an lt1, they run hot for efficiency and emissions.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Probably right seeing it is an older car. As to the heat issue, assuming that the gauge is right I'd flush coolant and check for the trash in the radiator either way It's either full of trash or not. Can't hurt to check