Just picked up a 04 fx4 with 5.4L auto, 164000 miles. Driving it around I noticed that accelerating from a stop the truck shutters pretty bad. But it doesn't do it all the time. And its only at low speed take off. from dead stop. Also at a stop with truck in gear, brake on, the engine sputters and wants to die. Now it doesn't do this all the time either. I was thinking maybe the trans was slipping? But would that cause it sputter at idle? misfire maybe? I'm not sure where to look first.

 

Is it throwing a code? Same thing happens with mine ('05 F-150 5.4 Triton), it caused the check engine light to fire, checked the code and am now going to replace all eight coil packs, got 'em from Amazon for $47.25.

 

No codes, and its not all the time. I'm almost thinking something with ignition.

 

Sounds like either plugs or cops. How old are the plugs?

 

No idea. I going to start with new plugs and cops. Just pulled of the cops and they all have yellow marks on top which I'm guessing is the originals from factory. Right now I've got plug holes soaking in carb cleaner, hopefully they wont break when I pull them out then.

 

Ok, replaced plugs, coils, cleaned MAF. Still have same issue. It sputters and shakes it seems most at low rpm when turning the steering wheel. It even died on me once. But still no codes. I'm wondering if maybe a vacuum line issue?

 

For mine, I replaced them at around 70,000, now have 109,000+ the plugs shouldn't be the problem, should they?

 

I wasn't sure. thought it was a good place to start. They looked pretty worn though. But turns out it wasn't plugs anyway.

 

Clean throttle body.

 

cleaned throttle body. took it off, cleaned out, reinstalled with new gasket. same issue.

 

I'm starting to think maybe its an issue with the front axle. From a stop accelerating in a straight line its fine. Accelarating and turning it feels like I'm driving over washboards. It almost feels like the front end is pushing. Could something be binding up in the suspension or axle?

 

Check the CV joints, mine does the same thing in 4x4 mode on dry pavement.

 

Ok, after more research I'm pretty much convinced its the clutch packs in the differential slipping. Found a ford tsb for it 06216. Although it doesn't give any info as to a fix....

 

get a 7 oz bottle of "Friction Modifier" at Auto Zone for $10. and pour into the rear axle housing. That should take care of the clutch dragging on corners.

 

Please tell me this was sarcasm or something I didn't pick up...