6.0 Wont start no codes

Dieselmafialb7

Dieselmafialb7

needs more air....
So I've been fighting a no start issue on a late 04 6.0. 102k miles

truck just died one day randomly while driving and refused to start again no codes

truck will build around 400-450 psi icp and try to start but just wont fire the rest way over icp % was 85% while cranking FICM had sync and 48v cranking

the fuel pressure showed over 60 psi from the lift pump so its getting fuel, did the bubble test passed with flying colors.

I put air to the icp port I thought I heard leaks around the stand pipes so did updated stand pipes and dummy plugs. now it takes forever like 3 or so mins of cranking to build icp to the 400-450 psi but still no start. also tried pulling the ipr out to inspect it no broken or missing screen even swapped it for kicks.

I'm not sure what else I should be looking for? 6.0s aren't my strong suit at all.

I don't feel its a hpop where it will finally build that much pressure?
 
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Since you done the stand pipes and dummy plugs have you charged the system with air again ? Because it still sounds like you have a high psi leak possibly.how does your low psi oil build ? Slow Or quickly
 
Yes I couldn't hear anything around the stand pipes but still sounded like there was air somewhere not exactly sure what to listen for either heard some minor air noise is normal? or should you hear nothing?
 
Low pressure I haven't pulled the oil filter out to see but it shows on the gauge after a couple cranks and soon as it has built it builds instantly again.

Guess it might be on the slower side it's got 5-30 amsoil in it
 
If the stand pipes aren't leaking air would I hear a air leak from the pump area with just the valve covers off?
 
With the IPR at 85% it's maxed out trying to build psi so I would think you still have a oil leak.I would hook the air back up and listen closely and give it a few minutes sometimes it takes alittle bit to get the oil blown out of the oil system to hear the leak clearly.you don't have a big leak with it building 3-400psi.
 
04.5ROHLING said:
With the IPR at 85% it's maxed out trying to build psi so I would think you still have a oil leak.I would hook the air back up and listen closely and give it a few minutes sometimes it takes alittle bit to get the oil blown out of the oil system to hear the leak clearly.you don't have a big leak with it building 3-400psi.
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K ill hook it up again. is there a fiiting that leaks by the pump or?
 
Yes there's a STC fitting that's bad to blown out on the 05-06 year model engines look on the passenger VC and see what year your engine is.
 
No STC fitting in the late 04! I mean there is an HPOP discharge fitting and it CAN leak, but it is not a common failure point.

Not sure I would rule out a failing HPOP.

When you did the air test, did you listen for any air coming from the oil filter housing or the turbo oil supply line?

Remove the oil fill cap, remove the CCV hose that goes into the air intake from the other valve cover, take a piece of heater hose and listen in BOTH spots after applying shop air to the ICP fitting. If you hear air coming from either one of the spots you are listening to, then it's probably a leak in one of the oil rails. If you hear air coming from BOTH sides it's probably the HPOP. hearing a leak from the oil filter (cap removed), it indicates a bad HPOP (same for hearing air from the turbo oil supply tube). Note - when the IPR is commanded closed (with the shop air flowing), you MAY hear a slight "POP" sound.
 
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400-450 sounds very low to start. hit it with some starting fluid while you monitor the HP oil. it should fire.. it will probably idle very low and die. and a zillion times to 1 you have a weak HPOP. its been a good long while since I had a good lap top on a 6.0 but Im pretty sure you need about 750psi for start fuel.

whats ICP readings
whats IPR readings
 
also you can have puck O-rings leaking
or if you tore or have a worn injector seal that the puck fit into. seen that leak oil pretty good.
 
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you need minimum 500 psi to fire. If you have had the HPO system apart, you are gonna need to get some battery chargers on it as it will take a fair bit of cranking to get the air out. (hence the long while to get to 450psi right now)

Just for fun, unplug the icp sensor and see if it fires. It will default to set value for pressure in the pcm instead of reading the sensor. If it fires up, you have a bad icp sensor. Also check for oil in the icp sensor plug, if there is some, replace the pigtail.

If that doesnt work, plug the hpop and dead head it to see what pressure it makes. If its in the 1000s very very quick, your pump is ok enough to start the engine.


If the pump is good and it still wont start, feed shop air to each head individually and listen for leaks.

I could say more but i bet you will find your issue before you get to this point lol


Oh and dont use ether on it, doesnt prove fuk all.
 
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did a re read.

450 at the ICP. you should have a log style oil rail. sensor on the passenger front. that's the control pressure reading right before it goes to the injectors. the IPR (pressure Regulator is on the IP). if it is working. moving from whatever % to your 85% its doing it job. thus in my small mind showing that you cant create enough pressure from the HPOP even at full demand on the pressure regulator. which is why you have a low ICP reading.

if you have a massive leak chances are it wont stay running even if you hit it with fluid. BUT if its a weak HPOP it will probably run just have a dead pedal and wont idle or start by itself.
 
I forgot to mention I unplugged the icp sensor already to rule out a bad icp sensor.

I'll check and see where I hear air at and report back
 
I don't. poor guys have poor ways. hit it with a bump of starting fluid. if it fires and barley runs at part throttle after all the tests you have done. go for the pump. IDK what kind of software you have to look at this thing. I bet it fires right up and shuts back down.
 
sootie said:
you need minimum 500 psi to fire. If you have had the HPO system apart, you are gonna need to get some battery chargers on it as it will take a fair bit of cranking to get the air out. (hence the long while to get to 450psi right now)

Just for fun, unplug the icp sensor and see if it fires. It will default to set value for pressure in the pcm instead of reading the sensor. If it fires up, you have a bad icp sensor. Also check for oil in the icp sensor plug, if there is some, replace the pigtail.

If that doesnt work, plug the hpop and dead head it to see what pressure it makes. If its in the 1000s very very quick, your pump is ok enough to start the engine.


If the pump is good and it still wont start, feed shop air to each head individually and listen for leaks.

I could say more but i bet you will find your issue before you get to this point lol


Oh and dont use ether on it, doesnt prove fuk all.
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Nice post sootie. 03 and 04 pumps are known for their higher than normal failure rate. Hard to do a dead head test though.

Anxious to hear the results of the air test.

If it is the pump, the Adrenaline pump is the best. terminator makes one also that is getting some decent reviews (and cheaper I believe).
 
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