This weekend my wife's 05 F150 5.4L went into engine failsafe mode for some reason. We have no idea what may have caused it. It barely runs now, feels like it's only running on about 3 cylinders. Anyone else had this happen?? I hope it's nothing major, as i just had to put $1,300 into my 03 SDuty !

 

How were you driving before it went to failsafe mode? Were you slowing to a stop, accelerating, idling? This has happened to several people slowing to a stop, including me. Did your Check engine light come on? If so, what codes came up? When was the last time your fuel filter was replaced? There are a lot of very smart people on here so someone will probably be able to steer you in the right direction.

 

limp it to the nearest car parts store and have them pull the codes unless you have a OBD II reader. From there we can help you troubleshoot the problem down. Otherwise it's just a shot in the dark.

 

I'd be careful driving it anywhere. Being an 05', might be injector related. I'd have it towed to the dealer and checked out. Driving the truck with the fuel injectors screwed up can damage the motor.

 

We limped it to the dealer (only 10 miles) and dropped off yesterday, just waiting to see what is going on? Judging by the way it was running i would guess maybe an injector, but i am not a mechanic. Will let you know.

We did have the edge/att. on it, you think that could have had anything to do with it?? I forgot to pull the codes before i disconnected it, to see what it said. Thanks for the help.

 

edge malfunction isn't likely. Guess we just get to wait and see what the dealer says now.

 

Sorry, it has taken me so long, got it back from the dealer later that day, they reflashed the computer and it runs like a top again now. I haven't tried putting the edge back on yet, figured i would take the chance to update it to the latest/greatest programming and see what happens. They explained it to me like a computer getting a power surge, and losing some or parts of it's programming? Anyhow all seems well, and it was a cheap fix compared to what i thought it might have been. Thanks for the info.

 

Just 2 weeks ago I had a coil and all plugs replaced. It started acting up again the other day and one of my plugs looked like it went through a bombing. About a 1/2 inch of it was gone. My truck only has 45k on it and I've had it since July and already dumped about 800 dollars in it. I'm off Friday and I'm trading the junk in.

 

Unless you set the rig back to stock before handing it over to Ford I'm afraid you may be SOL on "reusing" the Edge. Good to hear everything worked out and the rig's up and running again though.

 

i just had the failsafe error pop up this weekend, i had just started it, from being outside all night, and it popped up right away. it never ran on 4 cylinders (if it did it wasnt long) and it had full power right away. i reset the error and it went away, and my CEL never came on.

the guys in this thread say it happens when the engine is too hot, but ill b damned because it was -24C (-12F) where i was so it was nowhere near hot.

https://www.f150online.com/forums/en...-failsafe.html

is the fuel filter a common problem with this error?