Hello all, I have a 7.3 Diesel that is a crank but no start situation, the truck ran great up until it got a little chilly one night then I went to start it the next morning and it would just crank over, since then we have had a few warm days and I’ve also put new batteries in it just as an extra safety precaution because they were getting a little older anyway. A couple things I have checked out were the ICP sensor and also the glow plug module. I don’t have any codes showing up on the OBD2 so I figured I’d come to this forum to see if I could get any extra pointer for things I should possibly check out next.

Thanks in Advance

Shawn

 

It is important to know if the glow plugs are actually working.
You can unplug the wire that provides power to each glow plug .. Then with a meter measure the resistance. If the reading doesn't change to some kind of resistance, the glow plug is shot and needs to be replaced. There are 8 of them so that is a good place to start. If they are all measuring good,then we need to know if the glow plug relay is working.You can do this test with either a test light or voltmeter. Before going any further, let us know what you get.

 

Have you replaced the cam position sensor (on front flywheel)? I went through several with my long gone 95 F250) Only other part to check is the fuel solenoid and fuel pump. You can check fuel delivery by pulling the top fuel filter and have someone crank it over while you watch inside the can, Should be a big inrush of fuel into the housing.

 

I have not replaced the cam sensor, so I could try that next but I have tested the glow plug modular and the ICP sensor so those are functional, I did also take the fuel filter out and turned the key forward seems to be getting plenty of fuel.

 

I don’t have any codes pulling up on the scanner either, that was the other thing making me question the cam pos sensor

 

Instead of possibly replacing good parts and still having the same problem,
consider checking the glow plugs and relay.

If you have ,or have access to a multimeter it only costs you a little time and effort.
These are simple checks and the engine will have a starting problem if these plugs are are not working.

There is an intake heater that if you should decide to use starting fluid , it can cause a small explosion in the intake system and blow the air cleaner assembly apart .Do not attempt to use starting fluid.

 

What are you using for a scan tool? Most of the cheap ones don't read codes thoroughly. Torque Pro or ForScan (mainly ForScan) are the best values for what you get (ie almost free for a smartphone download and around $35 for the adapter).

Are you seeing an rpm when you crank? If so, what is it?

Are you getting smoke while cranking (after about 10 seconds)? If no smoke then no fuel is getting into the combustion chamber.

It would be good to know what the EOT temperature is showing at KOEO. If it has failed high, glow plugs won't operate.

Also, it woud be good to see the cranking ICP value (500 psi or more required to start), and also the injector pulse width command when cranking.