I have a 98 F150 with 92,000 miles. The other day I went to get a bite to eat, came out and the truck wouldn't start. It ran but spuddered and sounded similar to an engine dieseling when you shut it off. Then after several tries, it just kept cranking and not even firing up. I went to get a tow truck and after about a half hour, I tried to start it again, and it fired right up???? I drove it home for about 20 miles with my wife following me. No problems. I took it to my friends shop and we replaced the fuel filter, which was pretty plugged (never changed it). So, the truck is running good. Today, same thing happened, wouldn't fire over after turning the engine off. Same thing, started spuddering and wouldn't run. Waited about a half hour and sure enough it fired up and drove it home about 35 miles. When I got home, I turned it off and tried to start it again, and it started right up. I'm at a loss what could cause this. It's hard to diagnose unless it's acting the way it does when it doesn't start. Then after a while it'll run great and they can't diagnose it? Anyone have suggestions?

 

Next time it does this, hold the accelerator down a little bit. If it stays running, replace the IAC (Idle Air Control valve) It may be sticking closed.

 

LX- I did hold down the accelerator, it wants to keep running, however it just keeps studdering or sounding like it's running on two cylinders. Very similar to dieseling. Then I let it sit for about 20-30 minutes and it fires up and idles perfect? I was thinking about taking the IAC off and cleaning it. I did some research last night in the internet. It sounds like the IAC when stuck, doesn't let the idle come down or it's too low? It's odd, my problem seems to be very common among 4.6 and 5.4 engines, yet Ford mechanics can't diagnose it and codes usually show nothing is wrong. Any other suggestions or if someone else has experienced this, I'd be grateful to hear what it was to resolve the problem. To say the least, I'm nervous to drive my truck and stop anywhere for the fact I may not get home. LOL....

 

You might try cleaning the IAC, MAF and adding some good FI cleaner to the gas. My Windstar does this occasionally. It almost acts as if it has a stuck injector or something.

 

the MAF may be dirty. do you have a oiled air filter???????? maybe fuel pressure regulator

 

ford 390- I'm running the cold air intake K&N filter. It's oiled buy very lightly. Looks like this could be a number of things????? LOL.... I'll give the cleaning a try and go from there.

 

That "no start" after shutting down with the little bit of rough running and dead, that's no fuel pressure, I'd bet.

Could be relay, connections, etc, but is most likely the fuel pump.

Hook up a gauge during the no-start condition and check the fuel pressure.

 

krewat- You hit it correctly!!!!. I contacted a friend of mine who works in the service dept of Ford. The engine did the same thing yesterday with the spuddering, etc, but this morning, it was totally dead. It only cranked but wouldn't start. Anyways, he suspected it was my fuel pump by my description of what it was doing. I cleaned the IAC, and every other letter of the alphabet as people suggested, just in case. It still wouldn't startup. He told me to turn the key to on without starting it, and check if I had pressure at the strater valve (the thing that looks like a tire valve on the fuel bar). I depressed the valve and absolutely nothing came out, no pressure, fuel, etc. So, it looks like I need a fuel pump. Interesting, he told me that they are having several trucks coming in lately for fuel pumps. He also said that gas companies have been putting more alcohol in their fuel and its drying seals etc.???? I also checked out the price for this pump and found out fuel pumps aren't cheap for these trucks. Any ideas where to save some money on a pump and maybe some advise on changing this beast without dropping the gas tank on my head?

 

The other option is to remove the bed to access the pump. They aren't cheap because they come as a complete unit with housing, pump, fuel sending unit, etc.

 

No kiddin..... The best price I got for a Ford unit is $260.00. Right before XMAS, this really hurts.

 

Try aftermarket. Should work ok too.

 

Where exactly is the check valve?