6leakertweeker
New member
I'm kind of stumped by my truck. Its running really rough and having a hard start hot or cold. All the readings look fine and no codes but my HPOP pressure at idle is anywhere from 1000 to 1300. Could this be a IPR problem?
High HPOP Pressure????
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6leakertweeker
New member
IPR is at 15% cranking, 25% at idle. I'm getting 1300 psi cranking and its come down to 675 at idle finally. When you first start it, it will rev up fine but runs rough. As soon as it warms up you press the pedal and nothing happens. It takes like 15 seconds for the rpm's to start building. IPR is coming up with HPOP and it'll get close to 3000 psi under heavy acceleration. Still have no power and a heavy miss. I think i hear a slight click back by number 8 or 6.
when you roll into the pedal (when it won't actually increase rpm)....are you seeing a corresponding rise in desired ICP, increase in IPR%, increase in ICP_actual pressure...as well as increase in Accelerator position(volts or %)?
either way...none of those items would cause a miss...a miss is either an injector or an engine problem...there isn't a sensor, valve or doohickey on these engines that would cause one inj to fire differently than the rest.
This sounds awfully similar to the 100 phone calls I get every day...about the FICM voltage being low...
but...if FICM voltage is fine..then it's an injector problem, )unless the engine has a mechanical issue)< low compression, etc.
extremely high ICP can make a truck sound choppy, very 'crisp'..but not rough nor a miss...
and assuming you don't have a constant CEL/SES light on...means that the electrical connections b/w the FICM and the injs are fine.
your idle pressure & IPR% look spot on...btw..
Assuming FICM voltage is good...check fuel pressure...but if there isn't a FP (or fuel quality) issue..then it's inj/engine related...
either way...none of those items would cause a miss...a miss is either an injector or an engine problem...there isn't a sensor, valve or doohickey on these engines that would cause one inj to fire differently than the rest.
This sounds awfully similar to the 100 phone calls I get every day...about the FICM voltage being low...
but...if FICM voltage is fine..then it's an injector problem, )unless the engine has a mechanical issue)< low compression, etc.
extremely high ICP can make a truck sound choppy, very 'crisp'..but not rough nor a miss...
and assuming you don't have a constant CEL/SES light on...means that the electrical connections b/w the FICM and the injs are fine.
your idle pressure & IPR% look spot on...btw..
Assuming FICM voltage is good...check fuel pressure...but if there isn't a FP (or fuel quality) issue..then it's inj/engine related...
6leakertweeker
New member
Well I've got it narrowed down to a FICM issue and possibly a bent push rod.
My FICM is getting 48.5 KOEO, 48.5 cranking but when running its fluctuating below where it should be. I'm going to swap a different one on and see what happens. I pulled #8 and #4 injectors really ringed them and put new washers on. Im thinking 8 may be junk as one of the screens is missing on it. Going to pick up an injector and Ficm go from there.
My FICM is getting 48.5 KOEO, 48.5 cranking but when running its fluctuating below where it should be. I'm going to swap a different one on and see what happens. I pulled #8 and #4 injectors really ringed them and put new washers on. Im thinking 8 may be junk as one of the screens is missing on it. Going to pick up an injector and Ficm go from there.
PowerStrokeEnginuities
New member
Check your icp sensor, might be leaking oil thru connectors.
6leakertweeker
New member
The ICP is brand new. I think I got it figured out. I let it idle for about an hour and a half and went to move it and it was running fine. I think i just had air in the HPOP system. I've never had one take that long to bleed out though. All the readings are dead on now. Its pulling pretty hard again. I think 4 and 8 were leaking
FWIW, I have at least two FICM's on my bench that both test 48V+ for all 3 conditions (key on/engine off, cranking, and running) but both make the truck start like garbage and run like complete crap, until it warms up. Once it's warmed up, it runs fine. So sometimes even if they do read 48V they can still have other issues.
6leakertweeker
New member
Ya I know it. I'm pretty sure that's the other half of my problem.
