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Discussion Starter · #1 ·
I have a 94 F250 that will crank but not start. I have diy electric fuel so I have good fuel pressure, 60 psi. I used to drive it daily and it always fired right up. Lately it's taken more cranking and then it would fire up. Sometimes it would fire up then die then start right back up. Once I got it running it would be good for the rest of the day. I thought it might have been a glow plug relay issue so I replaced if with the monster relay but no change. If I crank it enough, the oil pressure gauge in the cab reads so I think the reservoir should be full. The tach reads so i think the cam sensor should be ok. Batteries are good because i have them on a charger. Looked at the wiring to ipr valve and it looks OK. Unplugged icp sensor and got a check engine light. I'm getting 12v to one of the leads going to the ipr valve. Need to check high pressure oil but need to get the right fitting tomorrow. Anything else I should check? Need to go pick some stuff up this week with a trailer and would like to use this truck if I can get it running. Thanks.
 

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My '96 did the same thing. I fought it for months, finally changed the CPS, and all was well.
 

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Discussion Starter · #3 ·
I think it might be my ipr valve. I have good voltage to it and the wiring to it seems to read like it should but I am getting 0 psi high pressure oil when I'm cranking it over. I changed the ipr several years ago so it might be pushing 200000 miles on it.
 

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A poppet valve stuck open can vent enough oil to cause a zero pressure reading. I suspect a severely-leaking injector o-ring could as well.

It never hurts to rebuild the IPR, and doesn't cost much.

If after that I had no pressure, I would plug one oil line and rig-up the pressure gauge directly onto the other line and crank it. If you build pressure, you'll know the problem is in the heads.

If still no pressure, put battery voltage directly to the IPR. Doing so should help you to eliminate the ICP and also the PCM as culprits.

Think it all the way thru - I bet you'll narrow down the problem fairly quickly.

Let us know how it goes.
 
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