So I have been chasing this high idle problem for a while now on my 2.8. I thought I had it solved when I found a small vacuum leak near the top of the tb. Runs better but I noticed my tb gets stuck sometimes and I took a closer look and I can actually wiggle the throttle blade assembly, If I'm standing right in front of the engine bay and grab the TB return spring and wiggle it back and forth it has a lot of play and gets stuck sometimes. I haven't checked my 3.1 TB to see if it has the same play but I doubt it does. I read something about some bushings or seals or something inside the tb shaft that wears out. Could this be the problem with my high idle.

 

I would just go and replace it.If it's that loose and getting stuck,it could be drawing in more air through the throttle shaft and because of misalignment.

 

[QUOTE=3.4 grape;6248091]I would just go and replace it.If it's that loose and getting stuck,it could be drawing in more air through the throttle shaft and because of misalignment.[/QUOTE


Yeah I'm pretty sure extra air is getting in there causing the issues.

 

when i had a tpi the throttle shaft bushings were worn to the point it would bind slightly above closed at idle giving me an idle rpm of around 1500. I'd have to blip the throttle a couple times on deceleration to make sure it shut correctly, if I didn't it would try pulling at a stop light with my foot on the brake.

since the shaft bushings were worn, it also created a vacuum leak from behind the throttle spring.

I bought a new BBK throttle body and it lasted a couple months since they're cheap Chinese garbage.

 

Dam thats's exactly what happens to mine. Cool guess I'll be hunting for a tb. Thanks for your reply bro.

 

So I swapped out the tb and same results. No change. I'm starting to think I may have an intake manifold gasket leak. I have another issue that only happens when cold. On cold start car hesitates real bad. I can wot and nothing happens then suddenly goes but hesitates real bad . Once it warms up it gets better, no longer hesitates, just feels sluggish but goes ok. What could this be. I was reading about the maf burnoff . What does this do? Although I no longer get any codes.