When I start my ranger it starts and dies 4or5 times then will keep running about 500-600rpm and won't excellerate, stepping on the gas causes it to almost die, after 2or3 minutes then it will rev to 1500 and gradualy drop to 1000rpm like it should. When its warm after setting for 30-60 minutes the rpm's do this again but it starts ok and does'nt die.

I have had it to a dealer; no fault codes,good fuel pressure, everything checks out good, Have replaced throttle position sensor,IAC, DPFE sensor, cleaned throttle body, new plugs,checked for vacume leaks, Just finished checking egr valve and MAF,O2 sensor all look good. $450.00 into it so far,pretty bad when ford techs don't know either.

Any Ideas from any one would be greatly appreciated, The only TSB that comes close is wiring harness driver side (frame) that could chaffe or rub through,checked it looks ok a little rubbing but not through the wiring

 

Honestly, it sounds like a fuel delivery issue to me. Is the filter new?

 

Thanks Mulletman

ford tech checked fuel pressure while this problem was happening good fuel pressure.,and new fuel filter.
Almost felt like fuel was just shutting off for a 1/1000 of a second this morning; fuel pump, fuel shutoff switch, fuel pressure regulator?

Guessing is getting expensive.