I have a 07 f150 with 5.4 3v when accelerated the rpm's goes up but does not go up on speed (fastest was 20 mph) any help?
So far replaced:
Throttle body
Fuel pump
And computer

 

Rpms increase, speed does not? That sounds like a transmission/torque converter issue.

 

Thanks for answering and the rpm's don't shoot up they take a while to go up no matter how much you push the pedal and it stops around 3000

 

Gotcha
How many miles are on the truck, and how old are the plugs?
Do you have any codes being thrown?
Was the problem there before you replaced the throttle body?
Have you cleaned or replaced the mass airflow sensor?
Have you checked for vacuum leaks?

 

Motor has about 60,000 miles no codes being thrown and no problem with throttle body before and there's a hiss coming from the drivers side engine will clen maf tommorow I was also told it can be the drivers fuel pump module can this be true?

 

That Hiss is a big clue. You need to find out what it causing the hiss.

What CE codes?

 

No codes showing up

 

It's possible that the FPDM is the culprit, but I doubt it. It wouldn't cause the engine to flatten out like that. Easy to check though. Drop the spare tire, and take it off the frame. If it's corroded real bad, replace it. If it only has a little corrosion, but no breaks or holes or anything, then it's probably fine.
I'm inclined to agree with Roadie, the hiss is a big clue! Sounds like you have a vacuum leak. If you didn't already, replace the throttle body mounting gasket (it's only a few bucks) and make sure the throttle body is torqued down properly. If that doesn't help, get a propane torch and check for vacuum leaks.

 

I'd suspect clogged cats or another major exhaust restriction.