So a few weeks ago this started. I can start the truck in the morning, no problem. If i drive a little or a while, and try to start it again, it will only crank and not fire. Cycling the ignition on/off has no effect, but I have discovered I can always get it to restart if I floor it whill cranking. Then it will start right up. Would this be injectors losing pressure, Fuel Pump, or Fuel pressure regualtor, or something else? It works fine when running-plenty of power and no issue to speak of. Any and all advice and ideas appreciated.

Sorry- Truck has 156000 on the motor and chassis.

 

Have you tried pulling the codes?

 

it could be any number of things. i have a '95 5.0 and had the same problem. it could be your fuel filter, pump, lines or any number of things. is it a manuel transmission or automatic? your alternator could be going bad. but the best idea would to pull the codes and see what they say. i know here in texas o'reillys auto parts store lets you rent a code reader for free and is very easy to read. you don't even need a code book it spells it out for you and if you need any help they can explain it to you at the store. also with the 5.0 the cylenoid has a bad problem going out allot so also check that.

 

Pushing the gas peddle to the floor when starting puts your truck in the "clear flood" mode. The injectors quit firing until the truck starts or your foot is lifted. Maybe you have a bad injector(s). This would help explain it being easy to start (no flooding) in the morning.

 

I was wondering the same thing bandbford. Me thinks it is time to pull the codes and see what they say. I suspect that with 156000 miles on the engine,those injectors are likely original. Thanks for the great Ideas, I am sure it has to be one of these things.

 

Forgot to add, I have noticed since this started the truck knocks alot more under load when i really get on it then it used to.... does this help anybody put some more pieces together?

 

GET THE CODES. thats all you can do at the moment. it could be so many things that no one can tell you until you get the codes. it sounds like you are either getting too much gas or not enough. so it does sound like a fault in your fuel system but the best thing you can do is get the codes read. either do it yourself or take it too a shop and have them tell you whats wrong.

 

I have finally gotten around to running the code reader on the truck today, and here are the results:
KOEO: 111 (Pass)
Continuous Memory Codes: 111 (Pass)
KOER: 111 (Pass)

So it looks like all the sensors, etc are good to go. Now it gets a little harder. Please anybody, with thoughts on this? The problem continues unchanged. Could this be bad injectors/Leaky? I will appreciate all the wisdom you have to offer.

 

When was your last tune-up? Mine did this and it was a bad distributor cap.

 

Last tuneup a little less than a year and 6500 miles ago, new cap,rotor,plugs,wires,the works. I would be surprised if the cap was bad already?? (motorcraft) Any other ideas.

 

Dirty injectors, Excess alcohol in your fuel? Have you checked the fuel pressure regulator?

 

Solution has been found. The fix was the ECT Sensor and the Air charge temp sensor. I think the ECT alone would have done it, but I bought both from the same crappy supplier when the problem started, so I bought both as new Motorcraft parts. Problem solved. Economy is good again, and truck starts right up every time.