I have a 2005 f150 FX4 4x4 101,000 miles on it and under acceleration, the engine shutters/stutters between 3,000 and 4,000 RPM’s but settles down when you let out of it or once its above 4,000 RPM. It does it when under hard acceleration from a start or if you gun it on the freeway to pass people. It has never thrown a code though. I have replaced the spark plugs,coil packs,fuel pump and transmission service at 75K. Any help or ideas would be great!

 

Could be a low-grade random misfire - below the threshold that triggers a CEL.

However, there will still be stored pending codes - accessible via an advanced scanner (Mode $06)

BTW - is that WITH or WITHOUT yer Edge programmer canned tuning?

MGD

 

I had the Edge tuner at stage 3 and returned it to stock and it does the same thing.

 

Keep it stock until this is sorted. Canned tuning and a misbehaving truck is a recipe fer grief.

Time to get those codes.

Fer chits & giggles, take a peek at ye FPDM...

MGD

 

My 04 is doing the same thing now that other things have been fixed, ie. vacuum leak at intake. Check engine light will flash but then goes off. Only does it when under a load, going uphill, getting out in traffic, etc. Havent checked the FPDM, thing I will do that tomorrow.

 

Took the truck to a shop and the tech drove it with a scanner on the passenger seat and no code were found,injectors,coil packs,fuel pressure all were with in range and no misfires were stored. I installed new plugs,packs,maf,intake manifold,FPDM,throttle body,knock sensor all before the fall of last year. I even with to the transmission shop this morning and they thought it was a misfire as well,so what gives? Anyone one else had an issue like this?