Ok guys, this has happened to me a couple of times, and nobody can seem to find out what's wrong...

Get in my truck, start it, and it dies right away. Start it again, and it dies again.

Process repeats.... I CAN keep the truck running by keeping my foot on the gas, but this obviously makes it a difficult way to drive home from work....in rush hour.

Guess what? I get home, shut off the truck, restart it, and it idles just fine. WTF?

Truck was recently tuned up, new air and fuel filters, and fuel system pressure was tested and is fine. No check engine light is coming on, and computer shows no indication of anything going wrong....

I'm stumped at the moment, and unless I can duplicate the exact issue at the dealer and /or independent mechanic (I've used both...), it's proving nearly impossible to fix.

Any ideas?


Pat

 

Have you checked the IAC (Idle Air Control valve)???

Very common issue with the 5.4L.

 

Same problem I had with my 4.6, the IAC was the cure. Take it off and use some carb spray to clean it out.

 

Ditto AjRango.

Next time you have the problem, tap the IAC with a firm object, ie screwdriver blade, and see if the engine starts right away. The IAC is a little ~ 2"x4" part that is attached to the top side of the Throttle Body on the firewall side. It is kinda hard to get to, but you can take it off with an 8mm socket. Once off, spray carb cleaner into the innards to clean out carbon deposits. I did mine and cleaned the TB and the idle is smooth as silk without anymore dying.

Good Luck.

 

Had the same problem. Spray some carb cleaner inside the TB.

 

Cool, I'll give that a shot tonight.

For some reason, neither the local Ford dealership nor my regular, independent mechanic thought to check that out.

My independent guy deals mostly with Fleet Chevy's though, so I have to forgive him somewhat....

Any ol' regular carb cleaner should work?


Pat

 

NO! Use throttle body cleaner. Look for an indication on the label that it is safe for oxygen sensors.

Trust me.

 

valvoline carb/throttle body cleaner is what I used, it doesnt really matter a **** load as long as you blow out the excess with some compressed air. Good luck, Im sure it will work fine