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2002 7.3l no start troubleshooting

Pt_Ranger_v8

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2002 2wd excursion, 330K miles, original everything, reman hpop @70K miles (260 on that)

Truck a little sluggish, with mushy pedal after ~8 miles driving.
checked the oil, it's dirty (due for change) and at the bottom of the hash marks.

Added about 2 qts of oil, started back up, drove another 4-5 miles, and it shut off, no restart.

Got it home, started troubleshooting.
ipr% starts @14.85%, climbs to 65% during cranking
oil pressure stays around 300psi during cranking
Rpms are above 200
volts are good

Check hpop oil level - oil is within 1" from top

Replaced ipr - no changes
pulled ipr sensor plug, scanner shows 2500psi, still no firing

Deadheaded hpop, I get surging pressure to 1-1.2k psi - but it's not constant - it bounces between 1k and zero.

Put 12v to the ipr, bypassing the pcm, no change.

Pulled valve covers, looking for leaky injector o-rings, I don't see any oil moving at all.


What else is left to check? I suspect bad hpop, but when I spoke to cncfab, he suspected bad injectors/orings. My testing doesn't seem to support this.


Is it posaible to have a bad motorcraft ipr, from the box? Anyway to test that?
 
How are you dead heading the pump, and how are you then measuring pressure? Any junk on the screen of the old IPR?

ETA: The ECM has to see ICP above 500psi before it will start firing injectors
 
Deadheaded the pump with a cap on one side, and a pressure guage on the other.

It would cylce to 1kpsi, then zero

pulled the ipr sensor plug, pcm saw 2400 psi, no fire.


new hpop on the way
 
i smell weak hpop

you put the spacer and the solenoid in the right order on the ipr when you put it in?
 
i smell weak hpop

you put the spacer and the solenoid in the right order on the ipr when you put it in?



cncfab agrees with you. The pressure peaking at 1-1.2k during cranking, then falling to zero means something failed internal to the hpop. That was my guess as well, since it went from 'fine' to 'sluggish' to 'dead' in a matter of 10 miles or so.


And yes, I installed the IPR correctly :laughing:

I should have my stage 1 hpop on Saturday or monday, so I hope that will tide my weak-ass injectors over for a couple more months :laughing:
 
I didn't see you mention swapping out the CPS. I'd throw one on just for shits and giggles as it would only take like 5 minutes to put a new one on for a try.
 
I didn't see you mention swapping out the CPS. I'd throw one on just for shits and giggles as it would only take like 5 minutes to put a new one on for a try.

well, I was gunna (and I still may) but both the dash tach, and the scan tool tach read rotation, so I'm assuming it works.
 
well, I was gunna (and I still may) but both the dash tach, and the scan tool tach read rotation, so I'm assuming it works.

Swap it anyways because it is fast and cheap and if you don't already have a spare you can throw it in the glove box for later. Also sometimes they do weird shit. I had one quit on me and the tach was still registering when cranking.
 
2002 2wd excursion, 330K miles, original everything, reman hpop @70K miles (260 on that)

Truck a little sluggish, with mushy pedal after ~8 miles driving.
checked the oil, it's dirty (due for change) and at the bottom of the hash marks.

Added about 2 qts of oil, started back up, drove another 4-5 miles, and it shut off, no restart.

Got it home, started troubleshooting.
ipr% starts @14.85%, climbs to 65% during cranking
oil pressure stays around 300psi during cranking
Rpms are above 200
volts are good

Check hpop oil level - oil is within 1" from top

Replaced ipr - no changes
pulled ipr sensor plug, scanner shows 2500psi, still no firing

Deadheaded hpop, I get surging pressure to 1-1.2k psi - but it's not constant - it bounces between 1k and zero.

Put 12v to the ipr, bypassing the pcm, no change.

Pulled valve covers, looking for leaky injector o-rings, I don't see any oil moving at all.


What else is left to check? I suspect bad hpop, but when I spoke to cncfab, he suspected bad injectors/orings. My testing doesn't seem to support this.


Is it posaible to have a bad motorcraft ipr, from the box? Anyway to test that?

Where did you get the Motorcraft? Unfortunately there are fake parts on Ebay and Amazon these days
 
Swap it anyways because it is fast and cheap and if you don't already have a spare you can throw it in the glove box for later. Also sometimes they do weird shit. I had one quit on me and the tach was still registering when cranking.

I'll pick one up. I still need a spare CPS anyway. :homer:




Where did you get the Motorcraft? Unfortunately there are fake parts on Ebay and Amazon these days

Amazon. It came sealed in a Motorcraft package, so :homer:

It *was* about $150 - which is a little cheaper than a dealer option, but not much :eek:
 
Well, after 5 hours, it runs. :smokin:

After speaking with cncfab a couple of times to verify my troubleshooting, we agreed it was the hpop - the big indicator was the pressure hitting 1k psi, then dropping to zero on both banks.



Ordered up their stage 1 hpop that was a) cheaper than a ford reman, and b)flow tested and came with a flow sheet. For my end goal with this truck, it will work beautifully. HPOP was delayed shipping out a day, but actually got here a day earlier than expected.
Followed a youtube video (DieselTechRon) on how to remove the hpop without taking out the fuel bowl, and it went pretty well. As I was installing everything, I realized I didn't have any RTV for the front cover, so I just put parts back on while my son did the parts gopher thing.:lmao:

Refilled the HPOP resivor with fresh oil, got the wife to crank while I looked for leaks and watched the scantool, and the truck started in about 5 seconds :eek:. Nary a hiccup or stumble. I can tell the difference driving it - now I can actually feel my worn injectors :lmao:


All in all, I recommend cncfab to anyone. They were helpful, polite, and didn't seem to mind talking me through the general troubleshooting 'tree' for the 7.3l hpop. :smokin:
 
Well, after 5 hours, it runs. :smokin:

After speaking with cncfab a couple of times to verify my troubleshooting, we agreed it was the hpop - the big indicator was the pressure hitting 1k psi, then dropping to zero on both banks.



Ordered up their stage 1 hpop that was a) cheaper than a ford reman, and b)flow tested and came with a flow sheet. For my end goal with this truck, it will work beautifully. HPOP was delayed shipping out a day, but actually got here a day earlier than expected.
Followed a youtube video (DieselTechRon) on how to remove the hpop without taking out the fuel bowl, and it went pretty well. As I was installing everything, I realized I didn't have any RTV for the front cover, so I just put parts back on while my son did the parts gopher thing.:lmao:

Refilled the HPOP resivor with fresh oil, got the wife to crank while I looked for leaks and watched the scantool, and the truck started in about 5 seconds :eek:. Nary a hiccup or stumble. I can tell the difference driving it - now I can actually feel my worn injectors :lmao:


All in all, I recommend cncfab to anyone. They were helpful, polite, and didn't seem to mind talking me through the general troubleshooting 'tree' for the 7.3l hpop. :smokin:

Awesome!

Also diesel tech ron is awesome
 
[486 said:
;n98862]

if you pre-fill them you don't have to crank as long on the first start

Good to know, just wondering why he mentioned checking the oil level in the pump.
 
Good to know, just wondering why he mentioned checking the oil level in the pump.

And with a worn front cover/oil pump it's possible for the HPOP res to drain on startup before getting refilled which will stall the engine and give you a no start.
Any time you have low ICP it's a good idea to check the oil level.

I had a truck that could not go 100 miles over 5000 miles before it would die on startup. I had a little funnel that I could add oil through.
4500 mile oil changes fixed that :laughing:
 
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