I posted about this a long time ago, but now I have some more idea about the source of the problem. What happens is that the gas pedal is really hard to push down at first and then it really smooth, so the car always lurches forward. Now I know it isn't the linkage or the throttle plates because the peda doesn't stick when the car is off. So what I'm thinking is that there is some pressure or vacuum building up inside the throttle body. So I don't know if there is a vacuum leak or something. Sorry about the long post but if anyone has any idea I'd appreciate it, Thanks.

 

I was talking to my firends dad, which is a mechanic, and he said that the injectors could be part of the problem. If those get worn over time could they be messing up the rest of the throttle body?

 

I doubt if the injectors are causing this. I would check for a vaccum leak, especially arond the base of the TBI. A leak will cause the idle to be higher than normal. An EGR valve will also make the thottle seem to stick by not closing all of the way when at idle.

 

I would try opening up the minimum idle air rate screw on the TBI. The throttle plates can stick with the engine running and not when it is stopped. There is alot of pressure from vacuum keeping it closed and makes it stick. I had a hard time getting the 4.3 TBI on my 3.4 Jimmy from sticking. The engine wanted to idle way too fast with the screw in or the throttle blades would stick with it running.

 

Like fast said, with the engine running there is alot of vacume pulling on your throttle plates. When the throttle shaft wears into the TB housing it tends to do just what your describing. It's funny how it only sticks when the car is running. Your best bet is to get a TB out of junk yard or ebay and put your injectors on your new TB to make sure you have the right size.

 

Yea, I'm planning on going to a junkyard to look for a TB. Any guesses on how much one would cost?