Hey all, newbie here....

I have a 95 F150, 5.0 302, 238,000 miles on it. Great truck but is giving me some fits. When I start up, it idles fine.....sometimes a little rough but mostly fine. When I put it in gear it still runs fine until I give it some gas, then it wants to die or really bogs down....if I give it more gas it sometimes backfires a couple of times then runs fine. Sometimes if I give it gas it still accelerates but slowly, then its like a supercharger kicking in and the truck accelerates fast, like I have just released something. I have scanned it and it has no codes, I have cleaned the MAF, new air filter, oil change, plugs, cap and rotor. I use Lucas Fuel cleaner in the gas tank but none seem to work.

Any ideas.

Thanks a mil......

 

Might want to do a compression test - with that many miles you may have some burnt valves.

Hmm - how about the plug wires?

 

Replaced plug wires last year. Does not do it at high speeds, runs fine except at low speeds.....

 

Follow this precisely:

 

I replaced the wires last year, the problem came up about a month ago but I will still check the routing....Thanks a mil, anyone else have any other advice??

 

That's a good diagram - our old rule of thumb was to try to cross wires as close to right angles as possible and separate parallel runs as much as possible.

 

Ok, heres an update.

Replace the idle air valve on advice, NO HELP.

All Data said it could be the MAF, unplugged the MAF problem went away. Replaced MAF with one from Autozone, NO HELP, truck ran ok until 40mph then wanted to die. Unplugged new MAF problem went away. Is this a bad MAF from the store or is there something I have to reset. I unplugged the battery for 1 hour after I changed the MAF just to be sure. With the MAF unplugged my fuel economy goes right out the window....

Any more advice??

 

check fuel filter and pressure
mitch

 

How would fuel pressure or fuel filter effect this if plugging in or unplugging the MAF has most of the effect?

 

Replace the defective M.A.F. sensor. Go back to Auto zone and get your money back. At least try NAPA, Carquest or Parts Plus stores, personally I prefer a Motorcraft supplier or the dealer to avoid the problem again, May be more expensive but better of in the long run. Good luck.