94 1500 5.2 won't start
 

this is my first post and I'm confused why my truck will not start. I started driving down the street 1 night and it just quit running and wouldn't re-fire. The next day I replaced the coil, nothing then I replaced the crackshaft position sensor and it fired right up, went to church that night came home parked it and went back out to goto the store and it wouldn't start again. The next weekend I bought a new battery and it fired right up. Drove out of the store parking lot and it died again! This time i sprayed starting fluid in it and it took off running, drove home and it quit again and now won't refire. I checked all fuses and the ASD relays, I spray starting fluid and get nothing. It has a manual transmission and turns over great.

First , welcome to the forum. Kinda surprised no one has given you a reply yet.

The first thing that comes to mind with such an intermittent no-fire problem is the camshaft position sensor, AKA pickup coil, in the distributor. When it won't start, do you have no spark? I'm guessing that's the case.

Second, you can see if the PCM has set any codes. I also have a '94 5.2, and in our pre-OBDII trucks you can get the codes without a reader by turning the ignition key on-off-on-off-on; the CEL will then blink out the error codes. One set of flashes will be the first number of the code, followed by a pause, then another set of flashes for the second number of the first trouble code. Finally, you'll get five flashes, then a pause, then five more flashes, signifying code 55 (end of codes).

The other main thing I think it might be is the PCM (computer) itself, but they seem to be pretty reliable, and I think a lot more cam sensors fail than computers.

Good luck with it.

I was thinking the camshaft position sensor after I read up on it more. Another thing I thought after I read more which is more expensive could be the fuel pump? If I understood right if it fails it can also cause a no spark situation? But gonna try the sensor first. I'll keep you updated.

If it was fuel pump, it should have tried to start when you shot it with starting fluid. Do you know if you are getting spark?

Changed the cam sensor or pickup coil today and still nothing. If I've tried to start the truck and it wouldn't start could the plugs have gotten fouled by gas? I read in my chilton's that if you're getting 0 voltage reading at the coil then to check the fuel system. If the fuel pump is not functioning does it shut down the ignition system also?

Buy a cheap fuel pressure tester, and check pressure.

Need to see what you are missing. Check for spark AT the spark plug end of the wires. Pull a couple of your plugs, and see what they look like.

When is the last time the truck had a tune up?

How about this for a strategy:

FIRST: If you can't remember when they were last replaced, put in a fresh set of Champion Copper Plus plugs. Do this no matter what the problem turns out to be. That might even be the problem. When my van was suffering from multiple problems - failing coil, failing crank sensor, fouling plugs - at one point it wouldn't even start. Fresh set of plugs, and it started right up and ran acceptably well. Yours might just be terminally fouled from all that's been going on with your engine.

Check your fuel pressure as Z suggested. Should be in the 40's.
Check for spark at the end of each plug wire as HeyYou suggested.
If you have a spark at the end of the wires, try the starting fluid again.
If your fuel pressure checked out OK, and it fires with starting fluid, I'd have to begin questioning the computer. It might be controlling the spark OK, but not the injectors.

I think I would also remove the new crank sensor and compare it to the old one. What brand did you buy?

Not sure the brand of cranksensor I got it from autozone, luckily it's under warranty and going to try it this after noon when the new one arrives. Checked the fuel pressure it was touching the 40's with just the key on. I'm changing plugs when I pick up the sensor today. I'll let everyone know what happens.