High Idle Blues

Hey, thanks for helping me out on my previous posts. My 90 with the 4.0 and the 5 speed is idling at 1300. Ive tried everything, different Idle Control Motor, Different throttle cable, the throttle butterfly is closing completely, I recently put a new 02 sensor in it, and I disconnected the batter for a few minutes to reset the computer. What am I over looking here? Could TPS adjustment be creating this condition? Thanks alot.

Ecarlcl

IMHO, I'd suspect the TPS before any of the items you mentioned...

So replace the TPS? Or adjust it?

Try adjusting the tps. I'm sure someone here has the specs. If not, for me lubing my throttle linkage worked for me.

i have the same problem in my 87... a direct result of soaking the engine with "gunk".... i'm thinking the TPS is the first in my line of troubleshooting if i ever get around to it.. i had an 89 a few years back that the TPS went bad on after it got wet also.... that time it screwed up my trany shift points so it was hitting all gears and lockung the converter by 30 mph... i'd try the TPS first.. do an archive search for TPS and there will be several good threads with proper adjustment method and voltage values.. good luck..
mike

Will do thanks a lot.

TPS Adjust for non-HO w/Manual Tranny

I just posted the procedure from the 1989 factory service manual (same for a 1990), a couple of posts up. Check there- save you some search time! 4xBob

If the TPS is not the case, check for vaccume leaks, ANY vacume leak will lead to a high idle, check the vac resivior behind the bumper, the charcoal canister the manifold, etc. you would be suprised what that will do to your idle