wpowell323
Petty Officer 3rd Class
- Joined
- Mar 29, 2009
- Messages
- 75
I have a f150 txrd that is off about 1000 rpm's at WOT. However it runs perfect and doesn't miss or sputter at any rpm. It use to run around 5800 and now only runs about 4800. The fuel pump in the vst locked up, so I put a new pump in the vst and cleaned the screen, when I put it in the lake it was off 1000 rpm's. Then I had the injectors cleaned. I replaced the fuel line and both fuel filters on the motor. I also checked the pickup in the fuel tank. I replaced the spark plugs, changed the gear lube and water pump and changed the engine oil and filter. I even went from a 17 pitch to a 15 pitch prop just to see and it still only wants to run around 4800. At WOT my butterfly's are open 87.4 degrees and the tps is at 4.086 according to the computer. I know the range on the TPS is up to 4.5, so should I adjust it so it at or very near 4.5 at wot? this is the only thing I can see on the computer that is not 100% within spec. Although I suspect at 4.086 it has already gone to full timing and such, but maybe not. I pulled the plugs and it seems to be running a little lean by the plugs. I have not checked fuel pressure, but it seems to have good power up to 4800 and pumping the bulb doesn't help and it doesn't speed up when you back off the throttle like some motors will when they are starved for fuel. Also the compression is fine on every cylinder. Any suggestions or what to look for would be greatly appreciated. I have access to YDS and am fairly knowledgeable with these motors, but this one has me stumped. Oh and the motor has 90 hours on it if that matters.