I have an 04 cab and chassis 550 dump symptoms leading to problem where rough cold start, miss, hesitate, rough idle, slow start cold and operating temp, then would miss periodicly, now crank no start. Bat voltage good, charging good, ficm 48v koeo koec, fuel bowl fills fresh fuel filters, oil level and change ok, no codes but engine light stays on during crank, no smoke during crank completely dry exaust, injectors cycle key on fuel pump sounds a little sluggish but has been sense i got it and been running that way. Im thinking hpop but would like to test to see if it is getting preassure without an oil presure gauge anyone have any ideas or can even tell me some more process of elimination cant i check voltage of icp to see if hpop is working and how. Thanks

 

Do you have an early 04 or late 04, if is the late 04 the ICP sensor will be on the pass side valve cover, early ones it is on the HPOP cover, alot harder to get to. Either way you can unplug it and see if it will start.
It will run in a limp mode, when it see no voltage it does this so you can get home or to a shop, if it starts then probably just an ICP sensor.
If it doesn't start then the next thing to check is the IPR valve also on the HPOP cover, remove and see if the screen is clogged or busted out on it, could just replace the screen if thats all it is.

 

also look into oil cooler and injectors mine would sputter once i got onto the freeway. my no start was the hpop but if your going to replace hpop update stc fitting and update stand pipes and dummy plugs while your there.

 

I did unplug the icp allready which is on the passanger side valve cover late model 04 and still nothing not even a sputter or try to start. Cant i check voltage at icp to see if hpop is building any preasure at all and if so whats the specs and what wire do i probe.

 

No, voltage at the ICP sensor will tell you if the sensor is good or bad, but if you unplugged it and no start, it's probably fine. IPR could be stuck open, or a high pressure oil leak, or the HPOP itself.

A scanner could easily show you what's going on. Monitor ICP desired vs. ICP actual, and check IPR duty cycle while doing all of this. ICP needs to be at least 525psi to fire. If ICP actual is low and IPR duty cycle keeps going up and up and up trying to build pressure and it's not happening, yeah most likely HPOP.

Your status says: X ford diesel tech... ???

 

thats what im trying to do now get one of my buddies when i use to work for ford to bring there lap top home so we can monitor those pids and i agree with you 100% mdub707 its probably hpop if i cant get a computer on it im going to pull the ipr out and check first i was going to check low oil preasure first it quick and easy to pull out oil filter now i wanted to keep in mind also why does my engine light stay on during crank by the way truck has about 79000 miles

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I was specialty and master deisel tech back in 04 before i got laid off and never went back now im wishing i would have thats what i meant by x deisel tech

 

The light is probably staying on now because it's probably throwing false codes, my guess would be for crankshaft position sensor and camshaft position sensor, these are typically thrown when a truck is cranked over a bunch and never starts, it just defaults and throws those, but they're not an issue. Probably wouldn't hurt to try and scan for codes too, despite if there is a CEL on or not.

You never worked on the 6.0's when you were a diesel tech?

Welcome to the site btw!

 

thanks and yea i started working on the 6.0 thats what i went to buffalo for training for but when i was active at the time 7.3s where what i worked on and they had all the bugs worked out of them at the time when the 6.0 came out ford was so sure that it was the next best thing yea ok the are idustructable but man alot of problems sure needed worked out on the high preasure oil side and an egr what where the thinking who cares about california emisions deisels burn nox from high exaust temps big deal right which don't go well with an egr but anyway i still have no codes still i think my next step is to pull the ipr and check the screen unless i can veiw some pids today and see whats really happening before i waste any more time. To be honest i love the 6.0l just need to get the updates done and its such i great motor i love the v vane turbo smarter than the dual turbo.

 

The scanner is the quickest and easiest way to check for sure. You can also do a "mechanical" test by applying air pressure to the high pressure oil system and commanding the IPR closed with a 12V source. The scanner can command the IPR closed, but only to 85% I believe.

If you can get your hands on a scanner, that's the way to go. Where are you from?

 

Thats what i need i have mostly everything else from when i worked for ford but that...i pour concrete for a living now though. Im from Pittsburgh so its snowing and i cant even go do snow removal because my truck is down its my luck