I haven't found any thing. I think maybe plugs and coils would b a good start?

 

I was having the same problem for the last while, RPMs were jumping all over the place, and then yesterday my truck started stalling randomly when I would slow down to idle speed (Intersections, stop signs, etc) So today I pulled the throttle body and sure enough it was filthy.. Cleaned the whole thing with throttle body cleaner, a rag and an old toothbrush, and now no more problems! I swear my truck is running better now then it ever has since i've owned it.. Throttle response improved noticeably and no more stalling or erratic RPMs! Try it for yourself, id say its the best place to start

 

My morning commute takes me through a 30 mph stretch. I just turn off the od right as im starting to slow down before she surges, like the tranny is searching for the right gear at slow speed. I dunno i might have trans problems though. 07 fx4 screw

 

Thanks for the help guys. I changed my fuel filter today and drove it about 15 miles, so far no more issues. Because my problem was sporadic, only time will tell. For those of you having similar problems, try replacing the fuel filter first before spending the big money on plugs and coils. You'll need the special fuel line disconnect tool, I bought the kit at autozone, comes with 4 different tools and only cost me $20, and $10 for the filter. Took about 15 minutes of time to do the job. Spend the $30 and time to do this as just one new coil can cost you at least $30-45, and one spark plug will run you around $12-14.

 

I know after replacing my tires on my 03 SCrew with 35s it did this. Turns out all it was is the shifting point programmed into the computer was causing it to shift over and over again at that MPH range.

 

Just for the heck of it and it's free try doing the diamonbird trick.......
Put the key in the Ignitiion and turn the key to the ON position, do not start the vehicle, now with the key in the ON position press the gas pedal to the floor very slowly once it bottoms out let off the pedal guickly, turn ignition to OFF and repeat these step two more times......now start your vehicle and go for a ride, report back if their is any good changes to your problem...I know it sounds like BS but it's not BS this procedure will reset your TPS and in most cases will solve any drivability issues. Give it a try it won't hurt anything and it's free.

 

I have an 03 f150 xlt 4.2 the truck has over 200k but I changed the motor over a year ago to another 4.2 it now the has about 50k the issue I am having is it's revving up and down when it's cold and it seems like it take awhile to heat up but when it's warm it runs great I changed the IAC motor that worked for about 1 weeks and the same thing happen, while the truck was off I pulled the plug for the tps then started it to see if the sensor was bad but it was the same I clean the MAF and still did it I check for an air leak and that seems fine, the engine light is on because I have no Cats on the truck they went bad so I put strait pipe on the cats are a lot of money and the only codes coming up are the 02 sensors, I thought maybe the IAC motor was bad again so to test it I started the truck and pulled the power power the motor to see if the truck shuts off and it didn't the idle just got a little low so I think it's good, does anybody have any advice to help me out? Thank you very much, I didn't bring it to a shop because I lost my job and job hunting and will need my truck thanks again all sorry couple more things I changed the gas filter and the spark plugs and wires and the coil pack

 

Probably a dumb question but what is the TPS?

 

Throttle position sensor

 

I'm in my truck now doing it but I still have the same issue I figured I would try it