I've read through a lot of posts regarding similar issues, and am running out of ideas.

Situation: Truck starts and idles fine cold. Once it's warmed up it periodically stalls when coming to a stop and will stutter (if not stall) when put in park. It will immediately start back up no problem. It throws no codes.

Attempted Solutions: I have cleaned the MAF, removed & cleaned the the throttle body, replaced (a very dirty) air filter. I am replacing the fuel filter tomorrow. The fuel pump driver module looks fine but will replace to be sure. I do have a fram oil filter and will swap out to a different brand at next change.

Truck Details: 2006 F150 SCrew Lariat 4X4, 5.4L. No engine mods.

 

seems like you troubleshooted a lot of the causes. maybe ur fram fuel filter was really dirty/defective some how. hopefully you get it fixed! gluck

 

clean throttle body. that use to happento me

 

You may want to try.......
disconnecting the battery,
then turn your headlights on,
then turn the headlights off,
then reconnect the battery.

This will reset the pcm and help get rid of the old fuel trims and start a relearning sequence.

JMHO

 

Thanks, I'll give that a try today.

 

Changed the fuel filter & reset the PCM. So far so good, just a 15min drive after so far so we will see.

I waited the 2 hours and disconnected the pump, ran it until stalled and gave it some extra cranks... I still stink of gas. But hey, if it works, I'm willing to stink for a little bit.

Out of curiosity, could the A/C cause rough idle/ stalling? No probs today, but no A/C, everytime I've had a problem the A/C has been on.

 

K so no longer 'so far so good'. I was hoping giving it a good drive would help it figure things out, but it stalled out coming to a stop tonight. I am about to leave for 2 months and will replace the fuel pump control module when I return. I may just go ahead and replace the throttle body as well.

I have noticed that the power steering seems a little wonky. It's a little rough and kind of tight. I had a power steering issue previous and it messed with the rpm's and general engine performance. There doesn't seem to be a leak, the fluid level is fine, I will do a check of the PS system tomorrow, any ideas where to start looking?

Thanks for all the help so far!

 

i had stalling issues with my truck twice. the first time was the throttle positioning sensor and the second time was a broken fuel pump/sending unit. mine threw codes both times though. does the check engine light come on when it stalls and go away when you crank it, or just not come on at all?

 

Doesn't come on at all. Occasionally I get a low fuel pressure flash quickly as it stalls. I'm changing out the oil today, pretty sure that's not it but might as well rule it out.

I'm also going to check for a vacuum leak.

 

Things just got worse. I went out to pick up a new pcv just incase. Went to 2 different places neither have a part number listed. Apparently it might be a OEM product only. Lame. By the time i left the last parts store the truck was having some major problems. It started stalling anytime my foot was not on the gas. Didn't matter what speed I was going... I got off the highway quick.

I was trying to eliminate the small stuff and work my way up the dollar ladder. Now I think I'll just replace the fuel pump driver module and throttle body. Any other ideas... I'm currently sitting in fast food joint letting thetruck cool down. :{

 

hmm maybe you should clean the throttle body.

 

After I got home I took some video and sound clips of the engine.

Audio of engine running 'normally':

http://www.youtube.com/watch?v=gonSCrjz1dY

And video when rough idle, but no stall.

http://www.youtube.com/watch?v=o1ljxDrokAo

Hopefully it will help with ideas. The fact that it continually gets worse the longer it drives makes me think air/ fuel... but I'm at a loss.

 

The PCV is part of the valve cover, no serviceable valve. I think you probably have a throttle body issue. If you had a vacuum leak severe enough to cause stalling, it should trip lean codes.

 

Thanks glc. the always helpful haynes manual shows the 5.4 with it serviceable. The fact that I couldn't find it should have tipped me off.

I agree about the throttle body, I was hoping to replace the gasket and tps today, but all my part vendors have to order it in.... So I have to wait 2 months, as I will be away.

 

My truck just started to do same thing as yours a couple days ago. The code it is throwing is Idle air control/low rpm. Hope that helps. Waiting for payday to fix mine.