I have an 02 f150 with the 4.6. it has a cai and flowmaster exhaust. i have been having a lot of problems with power. it seems anytime under a load, such as going up hills, it feels like my truck is being held down. right at 2k rpms. it feels like someone is pulling me back and there is no power at all. i just put in new u joints. any ideas what this could be? the coils are new and so are the plugs. my fuel pressure is right at 29-30. thanks in advance!!

 

i think the fuel pressure is suppose to be a little higher than that. what brand plugs? how olds the fuel filter? someone here will give you the fuel pressure specs. possible fuel pump, filter or cat convertor.

 

the plugs are motorcraft. the fuel filter is brand new too. would the lower fuel pressure cause this? i thought that fuel pumps were either good or bad

 

yup. the engine is meant to run properly with certain specs. certain exhaust flow intake flow and fuel pressure and volume. if any of those are affected then you'll see the problems that your having. i think the spec was something like 35psi minimum at idle.

 

those engine's like back pressure from the exhast, i got the cat's cut out of mine and lost alot of power, put a resonator in and got the power back.

 

i have had the dual exhaust for 2 years, but the problem only started about 3 months ago.

 

How many miles are on the truck?

 

97k

 

Well, that's just enough to seat the rings! Should run like new!

 

Try cleaning the Mass Air. Gumout makes a cleaner specific for the task.

 

My 2000 4.6L at 126,000 started having issues around the 2K mark, but on the freeway or getting on it seemed to avert the issue. Turns out my two frint cats were in the process of becoming plugged. You should be able to get the flow checked locally.
Good luck man