motor problem
Asked by d55cam Dec 14, 2014 at 11:36 AM about the 1999 Ford F-250 Super Duty Lariat 4WD Crew Cab SB
Question type: Maintenance & Repair
My 1999 ford truck has an intermittent problem.It takes spells where it just starts cutting out. You can be driving along fine and it will just lose power but it wont die. You come to a stop and it will idle but the second you touch the gas it cuts out.I i have had it do this and you wait and let idle for a while and it clears up and runs fine. It does have a little miss in it sometimes also i noticed today that. i cant get it to hold rpms any where. if you take it to like 2000 you cant hold it there it will just drop out. it also died today when i was warming it up just out of the blue. started it back up it cut out a few times and i havent been able to get it to do it again. Any Ideal please
9 Answers
There are tests that need to be run to avoid throwing parts at it. The pump(s), the power to them, selector valve, There are several ways this thing can go wrong. Identify all the parts in the system and inspect as you go. but inspect them all. Run your fuel pressure and volume tests and monitor when it dies to find where you lost what. These can be a real Tough one to just say...it's that ! ... since the filter is cheap, you can blow the contents back into a container, but know, if you are trapping dirt and have two tanks? it came from the tank to the selector, and then what made it through is in the filter. Pumps are not cheap. But I have seen trucks that needed multiple fixes or just both and a valve. Ford dealer will have experience to help or advise.
It is the lean symptoms that you are describing that make me say this, but the spark must not be shutting you down, it is possible you intermittantly lose it. What trouble codes are you getting?
Service engine light was on for awhile and it was running well but since it started doing this it went off now it will only come on when it is cutting out clicks on and off but as soon as it starts running right it go's off and stays off
Changed fuel filter seems better but still has a miss in it at high Rpms and a flutter when u let off the gas
Was there a good sampling of dirt in the filter? You blow the contents of the old filter into a container like 1/3 an antifreeze jug. white plastic is best. Are your plugs and wires decent, good quality and recent? What codes are in the computer for continuous memory and hard faults? When a code is set the thing goes into FMEM. You must read the code(s), pinpoint test, service as indicated, and clear the code. Skipping steps is bad. Aftermarket or cheapo plugs and wires do not last. Best results is motorcraft or equivalent. The CAFE regulation sticker advises spark plug part number and data. I am kinda suspecting your fuel issue is affecting the parts and hurting your HEGO's
I bet it is the wireharness on the side of motor. My 2001 power stroke did same thing. I found it by looking under hood when it was dark out and I could see arcing between the block and harness. I taped the harness with electric tape and problem solved .
