simpson1827

I have a 08 f150 5.4 that run good until I stomp on the gas say to pass someone. It downshifts rpms go up just dont pick up any speed if I ease into it without down shifting it picks up speed fine just wondering if anyone else has had this kind of problem thanks

fordguru

Poss intake restriction, throttle body issue, or VCT solenoids not advancing. Does it happen everytime?

simpson1827

Yes it does it runs fine shifts fine i bought the truck couPle months ago put about 300 miles on it the truck has 119,000 miles on it

fordguru

I will look into this and let you know

devbeau

I have an 06' FX4 with the 5.4. I have the same problem with no acceleration if I punch it. Did you find out anything on it?

fordguru

What if you manually shift it?

simpson1827

It helps but could be better

fordguru

When was the last time the fuel filter was changed if no intake restriction next fuel delivery. Change the fuel filter if you only bought 300 miles ago who knows when the fuel filters were last changed, 17.00 plus the tool 5.00 easy test and couldn't hurt even if it doesn't work but my bet would be fuel pressure at high rpm.

Buck

sounds like a tranny issue.

simpson1827

I will check the filter do believe it is new might take it to transmission shop have them drive it see what they think thanks for your help