idle question.Help
Thread Starter
Instructor
Joined: Feb 2005
Posts: 125
Likes: 0
From: york pa
idle question.Help
I have a 85 coupe car starts and runs awesome.The problem i have is the car searchs for an idle while there is a load on the engine(car is in gear)but is fine while in neutral any ideas.
here is a list of mods
msd cap,rotor,coil,8.5 wires
kn air filter
no emission parts
a small crane cam
descreaned maf
removed cold start valve
here is a list of mods
msd cap,rotor,coil,8.5 wires
kn air filter
no emission parts
a small crane cam
descreaned maf
removed cold start valve
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
I'm not completely familiar with the engine setup in the 85, but when was the last time you cleaned the throttle body and IAC valve?
Have run a vacuum check? On the LT1 it has a vacuum harness assembly that can be replaced.
Just a thought!
Perhaps some pictures? It stopped my chase for a rough idle.
Have run a vacuum check? On the LT1 it has a vacuum harness assembly that can be replaced.
Just a thought!
Perhaps some pictures? It stopped my chase for a rough idle.
Last edited by 93JetJocky; Jun 5, 2005 at 12:58 PM.
Instructor
Joined: Jun 2004
Posts: 155
Likes: 1
From: Melbourne Florida
Sorry no has answered as yet, must be a busy weekend. The first thing would be to check the O2 sensor and look for vacuum leaks(a can of carb cleaner sprayed on the hoses and connections), if you have vacuum leaks when you hit the right spot(leaks) the idle will change. Do you have a scanner you can hook up to the ADLD connection? If not you can usually get a loaner from your local autoparts supplier chain.
I would guess that is at least a good start.
good luck,
Woody
I would guess that is at least a good start.
good luck,
Woody
Thread Starter
Instructor
Joined: Feb 2005
Posts: 125
Likes: 0
From: york pa
i just replaced the iac motor took off the tb and cleaned it and installed new gaskets the car idles awesome while in park or neutral,but put in gear and the idle jumps from 740 to 440 rpms and threatens to shut off.While im driving the car(by the way runs great )i have to shift to neutral at a stop any help would be a apreciated
i am running motorsport blue to injectors (24 lbs) on a new stock regulator.Could that cause the odd idle?
i am running motorsport blue to injectors (24 lbs) on a new stock regulator.Could that cause the odd idle?
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Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
Well I'm more familiar with the LT1 systems, when you said park I assumed you have an auto, so I was thinking a vacuum leak with regards to that since its only misbehaving when its in drive at idle or declerating to a stop. I think late 93's and up had electronic transmissions so that wouldn't be a factor there.
It might be worth investigating.
It might be worth investigating.