The truck would run fine with less than 3/4 throttle and under 3000 RPM and when cold. When trying to accelerate hard the engine would miss or bog. I had engine scanned but, no code came up. I had fuel pressure checked and was a little low at 26 psi at idle and 30 psi at 3000 rpm. I did fuel pressure regulator first because it's easier and cheaper than fuel pump. I was also, told it cold be catalytic converter. Any suggestions would be appreciated.
It's sounding like a fuel pump. Have you got a fuel pressure reading at WOT with a load?
To check the cat hook a vacuum gauge up somewhere on the intake manifold. Start the engine and let it warm up to normal temp. With the vehicle parked record the vacuum at idle. Then quickly press the throttle to wide open and then quickly snap it shut. Do this three times and record the vacuum at each wipe open moment. Do it a fourth time and record this vacuum reading. If the forth reading is more then one in-Hg lower than the reading at idle then this could indicate a restricted exhaust (like a cat but could be a muffler). At this point I would pull the cat and inspect it.
2000 F-250, SC, SB, 4X4, Lariat, 6.8 V10, Auto, 3.73, Ford Racing headers, SCT X3 tunes by 5 Star Tuning
After changing fuel pressure regulator, I did a test drive. For the first few miles it drove good; no hesitation, engine revved to 4500 RPM in 1st & 2nd gear. Also, while driving in 3rd gear, I pressed the accelerator to the floor. The transmission downshifted and the engine revved up to 4000 RPM. I decide try it WOT one more time, and thats when it started to do the original problem; cutting out above 3000 RPM and anything under that seems to run fine.
When the truck is running fine the fuel pressure was 30 - 32 psi at idle and 38 - 40 psi with partial throttle and WOT. After a few miles the fuel pressure drops as you accelerate to about 15 - 20 psi.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company.