Won't start

[big dwag]

A friend of mine has a 1998 ford f250 with a 5.4 in it four wheel drive, I drove it to my house park it three days later i tryed to start it and it wouldn't start. I changed out the fuel pump filter, while it was off i turned the key to check the pump and no fuel came out, So i changed out the fuel pump and it still won't start. All it will do is turn over but will not fire up, Im not a ford man so i don't know what to do.

[rhandwor]

Originally Posted by big dwag

A friend of mine has a 1998 ford f250 with a 5.4 in it four wheel drive, I drove it to my house park it three days later i tryed to start it and it wouldn't start. I changed out the fuel pump filter, while it was off i turned the key to check the pump and no fuel came out, So i changed out the fuel pump and it still won't start. All it will do is turn over but will not fire up, Im not a ford man so i don't know what to do.

Look for a relay in the electrical center mounted on the drivers side and is marked when I had a 1997 I got a couple of spares at a scrap yard and checked them and kept in the glove box a relay for the A-C may fit for a check. Check if the schrader valve has a gas when depressed. If it does check for spark. You can try a used relay from another Ford that is running before buying.

[big dwag]

I have check all fuses & relays, it is getting fuel and i don't believe that all of the coil packs would go bad at one time. I have moved relays around to check other things to see if they worked and they do. and it still won't start.

[rhandwor]

Originally Posted by big dwag

I have check all fuses & relays, it is getting fuel and i don't believe that all of the coil packs would go bad at one time. I have moved relays around to check other things to see if they worked and they do. and it still won't start.

A common problem on these year Ford's is the camshaft position sensor. This will cause a no start. This pulses the coil so it will fire the plugs. On the front of the block close to where the camshaft is located. Held in place with one bolt. A crankshaft position sensor may be also bad or a loose ground wire.

[big dwag]

I 've been working on the f250 all day and got it down to its not getting any fire. rhandwor this is what i've been wanting to hear no one could tell me what causes the plugs to fire, the dealer wanted me to bring it out to them, I will check the cam sensor in the morning hope your right.

[rhandwor]

Originally Posted by big dwag

I 've been working on the f250 all day and got it down to its not getting any fire, I was told that it might be the crank or the cam senser or the computer. I don't think its the computer, So which one of these crank or cam senser would keep it from starting?

Camshaft sensor is more common and cheap.
Crankshaft will cause a no start.
A loose computer ground wire will cause a no start.

[big dwag]

I changed out the cam sensor today and the truck didn't start, I'll have to wait until wednesday to change out the crank sensor hope this works.

[rhandwor]

Originally Posted by big dwag

I changed out the cam sensor today and the truck didn't start, I'll have to wait until wednesday to change out the crank sensor hope this works.

Have you checked all fuses for the computer system?

[big dwag]

Yes all of the fuses were good inside and out on the engine compartment. The book said there were four places for fuses, But i only found two fuse boxes.

[rhandwor]

Originally Posted by big dwag

Yes all of the fuses were good inside and out on the engine compartment. The book said there were four places for fuses, But i only found two fuse boxes.

http://www.alldata.com/ sells a years subscription for around $29.95 they have good wiring diagrams.

[Jerry Irons]

Originally Posted by big dwag

I 've been working on the f250 all day and got it down to its not getting any fire. rhandwor this is what i've been wanting to hear no one could tell me what causes the plugs to fire, the dealer wanted me to bring it out to them, I will check the cam sensor in the morning hope your right.

Did you check the coil out? I had one fail in a 96 once that could still spark but not strong enough to fire the plugs when under compression. I stared at that engine for 3 days until I broke down and bought a new coil as a guess. Once I pulled the old coil out I could see the cracks in it, but they were hidden. I saw another bad one in a ford that caused a no start, when it was dark out, and you tried to start the engine, sparks were coming off of the top of the coil in plain sight!

Also you should probably check the fuel cut-off switch as well, the one that activates when you are in an accident, or go over a rough pothole...