I have just finished reinstalling engine and trans with new solid mounts and multiple other changes. The issue is when first started it searches then after a minute will settle down and idle very high. after it has ran for a while it will start searching again then die. On full acceleration it runs great. Engine light is on. I replaced a ton of stuff while i had the car apart, incl Idle control valve. I sent the injectors out to OK injectors for service. I don't have any type of scanner so i am just trying to figure it out before taking to a shop
Thanks, I will give it a spin. LOTS of info. I build mostly big block performance cars and while not totally lost i sure don't know where i am going. Very disappointed after spending 6 months in a full tear down and big bucks. I have owned this car for 16 years and want it to be right.
i understand, i am a pretty good old school mechanic but have trouble diagnosing electronic issues. I also have talked to a number of friends (Mechanics) and clearly they don't know anymore than i do. Will use the help the first of the week. Sure would be nice to learn something while resolving the problem. Thanks, Your help is sincerely appreciated.
The high idle could be a vacuum leak. As you noticed when you had it apart, there are quite a few vac lines going to a lot of places.
EVERYBODY with "impossible to find" high idle - check your Charcoal Vapor Canister!
V6 vacuum lines.
Just fixed a friend's 88 V6 that had a high idle (about 1800rpm) I checked all the vacuum lines. Found a leak in the Tee under the MAP sensor. Fixed that and idle came down a bit - was now 1500rpm. I was now sure I had no leaks anywhere else (engine had Dickman's stainless steel vacuum lines).
Removed the hoses to the Charcoal Vapor Canister at "purge" fitting end and capped the fitting. BIG difference. Removed the hoses at the Canister end and tested the lines with vaccum pump - they held vaccum OK. So Canister had faulty Purge Valve. Replaced canister and idle came down to normal. Drives better too!