Etdesign

I have a '94 F150 302 4x4 with about 55,000 miles. It's up on 38" Parnelli Jones tires with 4:88 Richmond gears. THe issue that I'm having is that when you are going a constant speed, the truck hacks up a hairball and downshifts for no reason at all while keeping a constant pressure on the gas pedal. The tac will jump to almost 4,000 rpm's then you have to let off the gas to get it to settle back to normal. It'll act up for a few days then goes back to normal for a few weeks. This cycle has been happening for a few months now. It seems to be more noticed when the weather is warmer out. Would a throttle position sensor do this? Any suggestions? Joe

Just call me Sean

iTrader: (1)

First check the computer for codes, this thread explains how: https://www.f150forum.com/f10/how-retrieve-trouble-codes-obdi-10907/ Sounds like a possible VSS problem.

fordfan1991

I had the exact same problem in my 94. it was indeed the throttle posistion sensor. its easy to replace. you just need to take off the throttle body. a shop did mine for $180

Etdesign

Thank you for the help! I chased this around for a bit and others suggested it might be an issue in the tranny itself. I though oh no! What is wierd, it really acts up when it is warm out, but it's only from time to time...