Loss of oil pressure, now truck is dead?

texascadillac42

texascadillac42

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04 F350, 11X,XXX miles. Truck ran perfectly up until the other morning. Truck would not start, didnt spend much time working on it, I just waited for a Snap On scanner to show up. Scanned it and got the normal EGR fault codes, and nothing else.

I then looked at the ICP while cranking it over, it was at 0, then jumped to 75 and stayed there.

While running the KOEO test, all of the solenoids and relays under the hood were clicking like they normally do during testing/scanning. So I figured I would try starting the truck one more time. I was still watching the ICP when it built from 75 to 399 to 6XXpsi and the truck fired right up. Let it idle for 15 minutes, scanned it again and got a P2285 (I think) code about ICP sensor low ......

Cleared that, started the truck again, and took it down the driveway at idle. Drove 1/8 mile, barely off idle and the oil pressure gauge dropped to nothing. Truck still running and idling fine, after 15 sec or so (just enough time for me to realize what was going on) the truck died. Tried to start it again and it started up and shut off.

I pulled the truck back to the shop, pulled the oil filter (which was dry) and had a buddy crank it over. The housing filled immediately up with oil, and drained out when I let go of the drain valve. I did this several times to confirm that it would fill the housing.

I am going to put a mechanical guage in place of the EOT sensor to verify what oil pressure I have. I have read that the oil pressure relief valve can cause problems, and that this is located under an allen plug in the bottom of the front cover. Where else should I be looking for problems? Thanks.
 
well if its pumping that seems to eliminate lpop failure.its possible that the oil pressure sensor has failed, or the ipr is staying open due to debris or some such
 
Thats what I was thinking, if its filling the filter housing with oil, the LPOP should be working, at least halfassed. If the IPR is stuck fully open, will that dump enough oil back to the pan to cause a no/low oil pressure condition? Do the IPRs ever fail in the fully open position? When performing a Key On Engine Off test with a scanner, would the IPR get cycled, possibly causing it to close, which would allow the truck to start (similar to what happened the first time the truck failed to start?) Thanks for the help.
 
What was the IPR duty cycle while cranking? And then what was it to keep the motor running?
 
it looks like you have good engine oil pressure so to check IPR. ground ipr ground wire forget what color, right to frame or good ground and it will automaticly go to full PSI if that doesnt bring up full psi you will need a HPOP thats the easiest way to check ipr. works every time
 
Or you could put the block off tools in the stand pipes and verify that you don't have a leak in either of the heads and isolate it to the branch tube and pump. Or o-ring in the pump cover. But hey, nothing is more fun than tossing on that hpop only to have to pull it all back apart for a stand pipe.

Also a good time to throw in a new set of check valves. Converting to the new style is also recommended.
 
Thanks guys, when I get back to the truck today I will look at IPR duty cycle while cranking, and will also check it if the truck happens to start. The only reason I am leaning towards an IPR valve is the way it instantaneously started after I ran the KOEO test, it seems like it is almost electrically related, not purely mechanical. I will post up my findings of the IPR duty cycle.
 
IPR duty cycle was 15% with key on, and 85% with key on while cranking. Truck never did start again. I am waiting for an adapter to come on Monday so I can replace the EOT sensor with a mechanical oil pressure gauge to verify that the LPO pump is working.
 
85% means its clamping off the ipr to try to build pressure. If you are filling the reservoir I would not worry too much about the low pressure side. Next Step is to start pulling valve covers to install block off tools to isolate the leak.
 
Thanks for the reply. Looks like that will be my next step then. Does that 85% mean the IPR is without a doubt closed off completely, or does it mean the PCM is asking for the IPR to be at 85%?
 
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