I Need To Ask A Few Questions......as I Posted One Time Before My Truck Started To Have Trouble Finding The Gears Back And Forth In The Rpms I Assumed The Tranny And Did A Fluid And Filter Changed And It Seemed Better For A While.now The Idle Has Started Getting Crazy High Then Almost Shutting Down.on Take Off It Sometimes Will Not Change Gears.when It Does I Can Be Driving At 50 Mph And The Thing Gears Down Like Im Manually Gearing It Down.i Guess What Im Asking Is Will A Bad Tranny Cause The Idle To Surge And Drop Or Am I Dealing With Two Seperate Problems? ......95 F150xlt 5.0 145000 Miles.thanks

 

Just a guess - I would suspect two different problems.

I would think the Idle Air control should keep the engine in check on the high RPM side, regardless of the transmission problems. The low-side RPM problem could be caused by something in the transmission, similar to dumping the clutch on a manual.

Suggest to fix one problem at a time - go after the transmission since you know you already have a problem there, then see if the idle problem still exists - may get lucky?

 

Thanks Wde3477.....i Almost Traded The Truck Yesterday.then I Started Thinking A New Tranny Is A Lot Cheaper Than A Monthly Payment.i Will Call Monday To Start That Process.i Dont Feel Good About Doing It Myself.......i Have Read Post About The Iac.is There Any Special Way To Clean It(solvents Or Cleaners).thanks Again.

 

I've always removed the IAC assembly from the throttle body and used carb cleaner around the ports, making sure the piston assembly moves freely.

Other users warn about getting carb cleaner on the Mass Air Flow sensor - ruins it. Not sure if your year has that. Need to use a special product for cleaning the MAF sensor so it doesn't eat the coating or whatever off - a search of other posts should turn that up.

I know what you mean about newer truck prices. Neighbor related that he always knows when I've gone looking - sees me out detailing my current ride afterward. I figure even a tranny job comes out to just a few months of new truck payments. But there is just something about new......

 

there is a special cleaner for throttle boddies and MAFs, it is safer than carb cleaner, and it wont eat the coating that is on them.

 

Thanks Ty I'll Look For It In The Morning.

 

I REMOVED AND CLEANED THE IAC THIS MORNING........I COULD NOT GET THE PISTON ASSEMBLY TO BUDGE.IM GUESSING I NEED A NEW ONE.SHOULD I BE ABLE TO MOVE IT BACK AND FORTH?.....AND WHAT IS THE BLACK CAP ON TOP OF THE IAC I CAN TURN IT BUT I WAS AFRAID TO TRY TO REMOVE IT

 

hmm, wasn't sure about this black cap thing, so I had to go have a look.

Mine doesn't have any black cap, other than the end with the electrical connector. Otherwise, it's all metal. It appears that the solenoid actuator assembly can be removed, and judging from the burrs on the screws, apparently I've done this in the past to get at the piston assembly better.

Did you remove just the IAC, or the entire throttle body? I'm just having a difficult time envisioning where this black cap thing would be, unless we're dealing with a different beast due to the difference in model years.

 

[IMG]file:///C:/Users/herb/Pictures/2007-09-24%20IAC/IAC%20002.JPG[/IMG][IMG]file:///C:/Users/herb/Pictures/2007-09-24%20IAC/IAC%20003.JPG[/IMG]

 

that did not work like i expected.well i guess its harder to post pics than i thought..........i just removed the iac...i did get the nerve to pull the cap off...it looks to be a cap for a port of some kind.....i put the iac back on and the truck still has a high idle for about a minute then the unsteady up and down returns....i may pay the 41.00 for a new one.....one thing about trouble shooting sometimes you end up with alot of new parts before you find the prob.i'll try to get those pics posted just to learn how.thanks for the input wde3477