HELP Wont Start After IPR Reseal

M

maxwedgehead

Member
Got a 94.5 7.3, truck isn't mine. Truck had a no start condition when warm. Replaced IPR o-rings, reinstalled, cranked on it several times, no luck. Replaced CPS, still no start, ohmed the coil on the IPR 10.6 so thats with in spec. Even hit it off ether a couple times and still won't run on its own, thinking stuck IPR valve but not for sure. Would like some comments or thoughts on what to look at next. Truck previously had new injector orings and glow plugs installed also.
 
Sometimes after introducing air into the heui system it takes a good bit of cranking to get running again. Drive about 50 miles or so to get all the air back out
 
I've cranked on it way more than any other time I've ever pulled injectors on a 7.3, cranked on it this morning 5 times about 15-20 seconds a time
 
That should have done it then. Have you checked to see if you have oil at the top of the hpop through the plug? Engine oil is full I'm guessing
 
I highly recommend the torque app for a 7.3 owner. $5 for the app and $10 for the dongle if you have a smart phone. Unlike our dodges you can monitor almost everything on a 7.3 with it
 
Drain the fuel bowl, pull the filter make sure it's getting fuel. Should take roughly 8-12 seconds to fill the bowl up with fuel.
 
You need to monitor icp with a scanner. If it doesnt see 500psi the ficm wont fire injectors which is why your not getting any smoke from the exhaust
 
cityredneck said:
You need to monitor icp with a scanner. If it doesnt see 500psi the ficm wont fire injectors which is why your not getting any smoke from the exhaust
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This is why I was asking^. Also as said before check to see if theres oil in the HPOP through the plug on top. How many volts are the batteries putting out?
 
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I had the same problem once. I had somehow broke the little tip off the needle inside the IPR. Still dont know how I managed to do that but I took the needle out of a spare IPR and it started right up.
 
cityredneck said:
You need to monitor icp with a scanner. If it doesnt see 500psi the ficm wont fire injectors which is why your not getting any smoke from the exhaust
Click to expand...
unplugging the ICP should set a default and should fire if theres hpop pressure am i correct?

SDS97_7.3 said:
This is why I was asking^. Also as said before check to see if theres oil in the HPOP through the plug on top. How many volts are the batteries putting out?
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Hpop is full of oil, never leaked off over night, batteries are new, also have a charger on them helping it

powerstroke95 said:
I had the same problem once. I had somehow broke the little tip off the needle inside the IPR. Still dont know how I managed to do that but I took the needle out of a spare IPR and it started right up.
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Well I had someone turn the key off and on and could not hear the valve it self move with a stethoscope, currently looking for an ipr someone has to try that.
 
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You can also manually energize the ipr by grounding one side and putting 12volts to the other. Unplugging it does default it but on a 7.3 i have had them where it still wont fire. Sounds like you need to try another ipr. Also make sure your pigtail connection going into the ipr is good. Its super common for those to go bad. You can get just the end at any ford dealer
 
maxwedgehead said:
unplugging the ICP should set a default and should fire if theres hpop pressure am i correct?


Hpop is full of oil, never leaked off over night, batteries are new, also have a charger on them helping it



Well I had someone turn the key off and on and could not hear the valve it self move with a stethoscope, currently looking for an ipr someone has to try that.
Click to expand...

Yes, if you unplug the ICP sensor it does set it to a default that the PCM sees. Well not necessarily, if the IPR is bleeding off too much from the HPOP you might not be getting enough to fire off. Ok good to hear that you have oil. If you have a load tester, test the batteries with the charger off, and then load test them and see what the voltage is. If it's not seeing a certain voltage, the truck will not fire. I cant remember the exact number for the life of me at the moment
 
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cityredneck said:
You need to monitor icp with a scanner. If it doesnt see 500psi the ficm wont fire injectors which is why your not getting any smoke from the exhaust
Click to expand...

You're thinking 6.0 psd, 7.3s don't have a ficm

For $15 you can monitor almost everything
 
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