I had this EXACT same issue in my 99 and the 93 that I just sold. Ranger is exactly right. Just clean your throttle body and you'll be problem free.

I removed mine from the UIMs and removed all the sensors and soaked 'em in gas for about 20 minutes and then lightly scrubbed with a soft bristle brush until all the carbon was gone. Bolted it all back together and it worked like a charm...no problems since. :wink:

I always wondered what caused that. I friend of mine said it was worn bushings (I laughed at him). But the carbon thing makes sense. Is it just me, or does this seem to be a gm thing?

I've seen this happen in Ford products too. My roommate in college and my brother each had a 98 Ranger with the 2.2 (I think that's the Ford 4-banger) and both trucks did it. Neither one took the time to clean the throttle bodies and just dealt with it, but it was very evident that it was there. I hated driving them because the trucks would really lurch forward when taking off from a dead stop.

The TB was not dirty, trust me I've cleaned it quite often lately. :wink:

It was the stop screw, I tune it a lot. But yes I could see in some cases where carbon build up would cause this issue.

The oily residue inside the intake is perfectly normal. It does not need to be cleaned out...little point in it as it will come back pretty quickly.

It is a mix of some oily residue from pullover thru the PCV system and some fuel residue from the "heavy ends" of the fuel that don't vaporize sufficiently to be pulled thru the system.

When intake manifolds had carburetors and throttle body injection on them there was a lot of raw gasoline sluicing thru the manifold so they stayed pretty clean and there was no buildup like that. With modern intakes with highly tuned runners and port fuel injection the buildup is common in all engines as there is no gasoline sluicing thru the manifold anymore to clean it out and the tuned runners tend to trap the material in the plenum as it would have to run up hill to escape thru the runners....

Along with this the EGR deposits exhaust gasses into the manifold. When the engine is shut off those gasses remain. One of the first things to cool down is the TB. Much like watching moisture condense on a cold window, the gasses that remain in the manifold condense on the backside of the cooler throttle plate. The moisture evaporates but the residue and carbon don't and build up over years.

I need to clean mine I have 150K and my pedal is sticking... how do I get to it? and what is the proper procedure?? TIA

Shane

What do you drive, year and model please.

2000 Bonneville SE