85 Idle issue
Thread Starter
Heel & Toe
Joined: Sep 2005
Posts: 22
Likes: 0
85 Idle issue
I'm pretty sure I've seen this discussed before, but could not locate any specifics doing a search so.....
I have an '85 with the 350. Recently, since moving to TX as a matter of fact (from OH), the idle has started to act up. When you first start the car it idles very rough, almost to a stall, for about a minute or two, then "something kicks in" and it smooths right out.
This happens even when the engine is warm.
I've replaced the cold air sensor located under the throttle body and the TPS to no avail. I thought before throwing more money at it, I'd check to see if there is something specific I should be looking for.
The car has 54K miles and otherwise, runs great.
On the TPS, when installed, it seems to stick on the side of the throttle body, so I put a small washer on the top mount screw and that freed it up. Not sure if the other one did that or not.
I have a full set of service manuals, but either missed or haven't been able to locate anything.
There are no "check engine" lights or anything else that displays when this problem occurs.
Thanks in advance for any help y'all can offer.
MacD
I have an '85 with the 350. Recently, since moving to TX as a matter of fact (from OH), the idle has started to act up. When you first start the car it idles very rough, almost to a stall, for about a minute or two, then "something kicks in" and it smooths right out.
This happens even when the engine is warm.
I've replaced the cold air sensor located under the throttle body and the TPS to no avail. I thought before throwing more money at it, I'd check to see if there is something specific I should be looking for.
The car has 54K miles and otherwise, runs great.
On the TPS, when installed, it seems to stick on the side of the throttle body, so I put a small washer on the top mount screw and that freed it up. Not sure if the other one did that or not.
I have a full set of service manuals, but either missed or haven't been able to locate anything.
There are no "check engine" lights or anything else that displays when this problem occurs.
Thanks in advance for any help y'all can offer.
MacD
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Sounds like it may be a sticking idle air control motor. You can remove it and clean it (I use Valvoline Syn Power, carb & throttlebody cleaner), then spray out the throttlebody bore where it sits and into the idle passages. Compress the IAC and reinstall with the gasket.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by MacD50
I have a full set of service manuals, but either missed or haven't been able to locate anything.
There are no "check engine" lights or anything else that displays when this problem occurs.
There are no "check engine" lights or anything else that displays when this problem occurs.
Just because the "check engine light isn't on, doesn't mean there aren't any codes set. Have you checked? Follow the trouble shooting charts for any codes you find. You've thrown (wasted) enough money chasing false cures.
RACE ON!!!
Thread Starter
Heel & Toe
Joined: Sep 2005
Posts: 22
Likes: 0
85 Idle Issue
Well, I've not made any progress. There were a couple times when the problem wasn't there at all. But that was short lived. Gonna scour my Helms manual and see if perhaps I can locate some info before proceeding further.
Instructor
Joined: Aug 2004
Posts: 109
Likes: 3
From: Just North of Boston Mass
Get a new chip. 85 chips are crap!
Get someone [there are plenty of people on the forum who can do it for you] to burn you a new custom chip for the computer. I chased this same problem for a long time. You can have the Idle speed set to where you want it. The factory or even the Hypertech chips are crap.
The best thing I ever did, you won't be sorry.
The best thing I ever did, you won't be sorry.
