trophyman

Thanks for the info guys.

trophyman

OK, I replaced the fuel pump, fuel filter, FTPS, and purge valve. Truck runs better but still not right. I can't accelerate quickly from a stop or kick it while moving. If I punch it hard from a stop, the engine runs up to about 2700 and starts sputtering and trying to back down. If I lift my foot and accelerate gradually, no problem, I can run up to 75 mph. But if I try to kick it from there the engine just bogs but not die. It will eventually pick up but only if I take my foot off the accelerator. ALSO, NO CODES THROWN.

Does this sound like clogged injectors? This truck sat for 7 years and I only started it occasionally. I'm sure that is what killed the fuel pump. The gas in the tank looked like crap. ANY THOUGHTS??

Fordfan2006

If change the coils and plugs and clean the maf. Use motorcraft parts from id recommend Tascaparts.com

trophyman

Yeah, it doesn't feel like ignition. More like fuel problem

Fordfan2006

have you ran injector cleaner in it? If not try that first if you think it's a fuel issue.

TRD-Toy

I would recheck your fuel pressure. IE pressure and volume. Under hard acceleration. Power brake or tape the pressure gauge to the windshield. Drive it. Pressure and volume ok?
Typically with a problem like this: WOT loses speed/rpm's, backing off the throttle slowly starts to accelerate. Fuel problem, restricted air filter or restricted exhaust. Sounds like it can't breathe!

trophyman

When I dropped the tank to replace the pump, I drained the old fuel and filled with fresh. I added a bottle of Techron to the tank, but that may take a while to clean dirty injectors.

trophyman

Agree, it does sound like all the above. That's why I'm leaning towards clogged fuel injector(s). I have an Air Raid CAI with new filter. I also have a Gibson cat/back system on it, and it doesn't sound odd. Leaving this truck parked, in my shop, for 7 years was worse than having driven it. Only has 61,000 on 2000 vehicle. Gotta get this truck going.

mbb

If injectors are clogged, you should show high fuel trim as computer is increasing injector duration to get the right amt fuel according to O2 sensor. If the engine wont run right, it would probably be out of range high and you would get code for that.

Pull the injectors and look in them for gunk, they are easy.

Your fuel pressures at vac/no vac were correct. You need less fuel presssure at idle when manifold vacuum is highest and more at high speed when manifold pressure is much lower.

trophyman

I really need to check the fuel pressure at speed. It feels like I'm loosing pressure at RPM over 2500. I have a new pump.filter on it. How often do the Fuel Pressure Regulator go bad on the 5.4? What program can I use to pull data from computer, e.g injector trims etc?

I use Tuner CATS to make adjustments to my LT/4 in my 39 Chevy with OBD1 data link.