Accelerates by itself

I have a 91 SC latley my Idle has jumped to 2000 at idle and 1000 when in gear but the weird thing is the car will accelerate to about 60-70 km/hr by itself which is weird and I am getting about 250 km to a full take i used to get 500+ so I am figuring its running rich and my throttle may be stuck open I thought it was the IAC but I only get code 125 which is the TPS Voltage changed out the TPS and still have the problem.

Any other ideas?

I am gettign desperated

sounds like a bad iac to me. does the engine make a sound kinda like a goose when you shut it down? if so definitely the iac. theres a plastic diaphragm inside of it that tends to rupture and cause the high idle you describe.

It's the IAC, my car does the same stuff. Shortly you'll hear some type of dying goose honk when you shut your car off.

Yep, the IAC is the cause to your problem. Same thing happend to my old 91 SC back in the day.

Shane

well took 107$ at a ford dealership to tell me that it used to make the goose honk but now the parts friend they put a piece of cardboard in there so my idle is back to normal now I just need to get the part tonight.

do you need a Gasket or something Between the IAC and the TB I just installed one and didn't put anything between because nothing was there before?

Just makign sure its on right.

Adam

Darkwhite said:

do you need a Gasket or something Between the IAC and the TB I just installed one and didn't put anything between because nothing was there before?

Just makign sure its on right.

Adam

Click to expand...

Yeah, there is supposed to be a gasket, but if the car's running fine then you'll be okay.