I need some help. I have a 2001 F150 supercrew with a 5.4. It wants to run at high idle, 1100 to 1500rpm. When I drive and get ready to stop it feels like it's still pushing. After stopping it then feels like it finally kicks down in gears. If I put it in neutral or park it then revs up to 1500rpm. I've replaced the TBS, PCV valve, cleaned MAF and cleaned the IAC and still nothing. Anyone have an idea?

 

I would double check for vacuum leaks...& maybe re-clean the IAC...If no success then re-scan for codes . Might be you have a bad Throttle Position Sensor TPS or bad IAC

 

Any DTC'S ? Or do you have a CEL illuminated?

If you haven't yet, get it scaned since it's free.

Sounds like you need the PCV piece back by the firewall and bhind the the plenum.

 

[QUOTE=jbrew;4847022]Any DTC'S ? Or do you have a CEL illuminated?

If you haven't yet, get it scaned since it's free.

Sounds like you need the PCV piece back by the firewall and bhind the the plenum.[/QUOTE

I'm not real familiar with a lot of this stuff. More of a learn as I go guy. Is this piece hard to get to?

 

DTC = Diagnostic Trouble Code
CEL = Check Engine Light

Scan = Auto zone scans your vehicle for DTC's free. Post back what they find. Write it down.

The piece is in the back, here -



Yours is a little different , but that's where they leak. You can put your hand back there while she's running and feel for the leak.

 

I read the code before I cleaned the IAC. It said it was the IAC and that's why I cleaned it. Then I replaced the PCV valve and the TPS. I bought the pick up used. It has 180000 miles on it. I don't know the maintenance history. Should I just get a new IAC valve?

 

Yes.

 

Changing out the IAC didn't work. Took it to a mechanic and sounds like it may be the torque converter.

 

Torque converter controlling idle?

That's a new one on me.

 

while your truck is idling take a can of carb cleaner and spray all the vac lines & joints.. If your idle surges or changes, you just found your vac leak... I would try that next..

 

Don't do that ^^^^ .You'll melt everything on top, your emission lines will melt first, before your eyes lol, and you could fry up all your coils with on false move. Burn insulation from the wires. That's THE WORST advice I've heard in awhile, can't believe it.

Anyway could cost yuh a lot of doh replacing everything. Also DO NOT use it in the throttle body. Not on these engines unless you disassemble and know what your doing.

Colored smoke propane or Mighty vac. With a vac tool you can check the entire vac haness and PCV quickly. They're cheap. A carbon cutter for cleaning.