I need some help from anyone out here. I have a 93 Ford Tbird with the 5.0 302 V8 motor. When I let off the brake, it just goes from 0 MPH to (lets say) 40 MPH. All without me even toughing the throttle. I have a new motor, 75mm MAF, 7"K&N cone filter, all kinds of new emissions parts, new Idle air control valve/motor, and underdrive pulleys. Does anyone think that the throttle position sensor is the problem or is the idle just too high? That's the only 2 possible reason's I can come up with. Please, I beg someone to help me. I know that it is NOT the MAF, IAC, or Oxygen sensors. I have run many codes on it and get nothing. I'm hoping that it is just the idle and I can turn some screw and get to go down. What is it supposed to idle at? Thanks for your help with this! Bill

For starters, what does it idle at now? Before you go and look for a problem with parts that can get pricey, check for a missing or loose vacume line. In my experience, I can say sadly that is all it may be. I had that problem with another vehicle I once owned. The idle was high and it just went on its own.

It idles around 1300 RPM. Checked all of the vaccuum lines. No leaks I can hear. Like I said all the sensors are brand new. the only one that isn't is the TPS.

Have you tried spraying WD-40 over the intake gaskets, air inlet gaskets, TPS (not in it, around it)? the other thing I would suggest would be clean the throttle body. Sometimes carbon or dirt will restrict the TB valve from closing all the way. Just make sure you get a can of TB cleaner that says safe for the coating inside. You said you replaces the IAC valve. I would check for air leaks at the gasket with the WD-40. If thats the problem the RPM's will get higher. Jack

Well today I took off the throttle body and noticed that someone has deffinitly adjusted the throttle stop. I can see marks on the TB where the adjustment screw is. Also, there are threads sticking up at the screw from being turned. I have checked all the gaskets and vaccuum lines also. I did have the car at the dealership for awhile. Maybe they did it when they were troubleshooting it. I will find out tommorrow. If they did, then I will get them to put it back where it was. Oh, by the way, where did WWW.tccoa.com go? I can't find it. Keeps sending me to some search page. Did they go offline? So if any one knows how to adjust the throttle stop on these TB's let me know.

I'm glad you found the problem. If by chance a TB from a 4.6 will fit, I have one if you need one. Sorry about the long message last time, just trying to help. Jack