I was driving, engine completely warmed up (30 minutes or so) and the engine died. (As if I had shut off the ignition) Will not restart.

No codes. Engine oil pressure during crank is good - getting ready to test high pressure system. Fuses and relays all okay. I verified the UVC Harness is completely hooked up - heard this is a common problem. Replaced Cam Position Sensor - also heard that this is very common and will produce common symptoms. Fuel pumps are delivering fuel fine to the filter and beyond. Still no start.

There is no fuel going into the engine - as I crank, no fumes at all coming out of the exhaust. Very different from a glow plug relay failure symptom.

Any thoughts would be very appreciated... I'm almost ready to tow it in for some help. :-(

Thanks,

SJK

 

May want to check the level in the high pressure pump resivor. May not have a level and theirfore won't fire the injestors.... Just a idea??

 

I just checked the level in the high-pressure pump resv and it was okay. I also just checked the oil pressure in the high pressure oil galley on one of the heads and it was only 250 psi while cranking - I was expecting more. Does anyone know what it's supposed to be?

 

Does the tachometer register any RPMs while cranking? If not, it is a strong indicator of failed cam position sensor. The sensor is located at about 10:00 from the front crank pulley on the front of the engine, more easily accessed from the ground than from above. One 10mm bolt holds it in.

Dave / Believer45

 

Wish I would have known that if the tach wasn't moving while cranking that it was the Cam Position Sensor... I put a new one in today and still no start. The tach did and still does register some RPM while cranking. Thanks for the thought...

 

Ok here goes some novice advice. At 250 psi that isn't even enough to drive the injectors. No wonder your'e not getting any fuel. So that leaves the HPOP itself and/or the little pressure control valve on the bottom of the pump. I would pursue whatever it takes to get good HPOP pressure.

 

Fixed the problem - thanks for all your help. Here's the details...

As mentioned in the initial post, the engine died and was delivering no fuel to the cylinders.
(1) I started with the Cam Position Sensor (CPS) - replaced it ($120) and still no start.
(2) I was told by a local powerstroke mechanic that they ran into a problem with the fuel heater element (just under the fuel filter) that shorted out, causing fuse #22 to burn. The injector controller is on the same circuit. I checked all the fuses in the truck and all were good. Still no start.
(3) The low pressure oil was okay - the idiot guage was coming up when cranking indicating that I was getting at least 7 psi. So I decided to test the high pressure oil system. I was only getting 250 psi.
(4) I asked the local mechanic if there's a pressure relief valve in the High Pressure system, and he said NO, the injectors act in this capacity. He said to first isolate the heads to make sure that an injector isn't bleeding off oil pressure. I tested the system disconnecting each side and still got the 250 psi reading.
(5) The high pressure oil pump rarely goes out - but there's this valve called the IPR Valve (Injector Pressure Regulator Valve). It screws into the bottom of the high pressure oil pump, facing backwards on the drivers side. My local mechanic recommended replacing that valve before pulling out the pump. To replace the valve, you must remove the fuel filter assembly.
(6) I put the new valve in ($250) and cranked it over to test the high pressure oil - it pegged my 3000 psi gauge.

Put it all back together and she fired right up.

Thanks again for your input. Hope this detail helps someone in the future!

SJK