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I am wondering if I am not losing my HPOP. Under an uphill load IPR hit 64.8% and the I start seeing ICP PSI drop to around 1500. Flat ground I can max it max the IPR to 64.8 but I have to really be flogging it. Under normal IPR % I have seen the ICP running up in the 2k range. Truck is not chipped. Reman injectors went in a couple of months ago. I have AE but left cable at my shop an hour away. Any ideas? THX
Lot's of variables. What do you consider a hill? What were you towing? Did the truck slowly lose speed as it went up the hill? How long of a hill? What's your rear gear ratio? How fast were you going to start and what were you're RPM's at the bottom of the hill?
Could be normal, or it could be an issue. A weak HPOP or leaking o-rings will show themselves on flat ground as well as grades.
Lot's of variables. What do you consider a hill? What were you towing? Did the truck slowly lose speed as it went up the hill? How long of a hill? What's your rear gear ratio? How fast were you going to start and what were you're RPM's at the bottom of the hill?
Could be normal, or it could be an issue. A weak HPOP or leaking o-rings will show themselves on flat ground as well as grades.
No load, long hill, 4.10, ZF6 trans. Started at 70 ish MPH and at the top 40 MPH at best. Hill about 1/2 mile long and if I were guessing 20% grade. Had no power to pull hill. Anything above roughly 1/4 throttle it felt like cylinder would drop out. On flat ground a WOT run will result in the same. I can hit 64.8 on flat ground and then watch the PSI drop to 1550-1650. No indicators of O-rings. Rebuilt injectors have less than 500 miles on them.
Who rebuilt the injectors and what brand of o-rings did they use. If they are/were not Alliant, then they very well could be reaching the end of their life at 500 miles.
Next, if they were not lubed properly or if someone just whacked the injectors into place then one or more o-rings could have been cut or damaged.
Do you still have your stock fuel bowl? If so, remove the cap and see if the fuel filter is turning black.
If it is, then, you have an o-ring problem at a minimum.
Do an "advanced" search or check the signature for "Tulgy" for the "CODY Test" which is a diagnostic test for leaking o-rings on the oil side of the injector.
Next, check your ICP sensor. Simply unplug it to see if the truck runs differently. You will not be able to rely on the data that you see due to it being a default PCM table instead of actual "live" data for ICP: it will simply allow you to see if the symptoms go away with it unplugged.
It would be very helpful to have some logged data for us to look at...
Fuel pressure can cause the same issue. There are screen inside the fuel tank that can become restricted that can cause similar symptoms.
Usually if oil pressure drops off too much, an CEL is set due to low ICP. That can still happen with fuel pressure, but there is no sensor and no corresponding code for fuel issues on these trucks.
Who rebuilt the injectors and what brand of o-rings did they use. If they are/were not Alliant, then they very well could be reaching the end of their life at 500 miles.
Next, if they were not lubed properly or if someone just whacked the injectors into place then one or more o-rings could have been cut or damaged.
Do you still have your stock fuel bowl? If so, remove the cap and see if the fuel filter is turning black.
If it is, then, you have an o-ring problem at a minimum.
Do an "advanced" search or check the signature for "Tulgy" for the "CODY Test" which is a diagnostic test for leaking o-rings on the oil side of the injector.
Next, check your ICP sensor. Simply unplug it to see if the truck runs differently. You will not be able to rely on the data that you see due to it being a default PCM table instead of actual "live" data for ICP: it will simply allow you to see if the symptoms go away with it unplugged.
It would be very helpful to have some logged data for us to look at...
This is a really screwy deal and a long story but the short is that the motor was put in by someone else and he messed everything up. He said an injector or 2 were bad AFTER the install because it would pour blue smoke on anything but idle. Gave me a set of rebuilt injectors and I put them in. I am not a novice mechanic and lubed them properly and carefully installed them. I will check the fuel bowl tomorrow but I am seeing NO smoke out of the exhaust. Will also check out suggested search.
What parameters would be helpful in a log? I have to drive an hour one way tomorrow to grab me cable to hook up the laptop.
Originally Posted by Sous
I cannot offer nearly as much technical advice, but there is definitely wrong with how the truck is running.
What led to the injectors being replaced? Was it preventive maintenance or were there problems with the original?
See above. Appreciate any knowledge and/or experience!
Originally Posted by F350-6
Fuel pressure can cause the same issue. There are screen inside the fuel tank that can become restricted that can cause similar symptoms.
Usually if oil pressure drops off too much, an CEL is set due to low ICP. That can still happen with fuel pressure, but there is no sensor and no corresponding code for fuel issues on these trucks.
This has been a 15 month ordeal. Hutch/harpoon mod has been done. When I pulled the tank it was clean inside. New fuel pump. Running Diesel Site fuel filter on the frame. I don't think it is a fuel issue because with my wife was behind me and she said the whole way up the hill it stank of diesel. Another friend of mine that has experience with these said that with low HPOP pressure the weaker pressure injectors would not fire properly and lead to a misfire (above I stated that it felt like cylinders were dropping out) due to improper injector spray.
All this started when the clutch grenaded when the trans took a dump. Before that I had been chasing a running issue ... MOST of that issue was because the PCM was for an AUTO truck. My truck is an E99 with a 2001 motor and PCM swap. Without getting into the NOVEL of a story that this truck has become I will answer whatever questions you may have. Truck has TONS and TONS of new parts in it. Earlier I did notice that it is running an original style ICP Sensor.
Sounds like fuel is not the likely culprit then. The problem is, with new injectors, it's hard to narrow things down. Some brands of new o-rings fail unbelievably fast. Some rebuilt injectors, even faster, but those usually give symptoms at other speeds or idle too. (usually).
A weak HPOP is rare, except on rebuilt units for some reason. Have you seen a tag or RTV on the front cover plate that might indicate it's a rebuilt HPOP? Usually the rebuilt HPOP issues are volume related, not pressure, so it's hard to diagnose at idle since you always get enough volume at idle or cranking to produce the pressure, but under load, as the volume falls off, so does the pressure.
I've only seen this happen on rebuilt units. Even from a reputable builder (who promptly took care of the problem).
Sounds like fuel is not the likely culprit then. The problem is, with new injectors, it's hard to narrow things down. Some brands of new o-rings fail unbelievably fast. Some rebuilt injectors, even faster, but those usually give symptoms at other speeds or idle too. (usually).
A weak HPOP is rare, except on rebuilt units for some reason. Have you seen a tag or RTV on the front cover plate that might indicate it's a rebuilt HPOP? Usually the rebuilt HPOP issues are volume related, not pressure, so it's hard to diagnose at idle since you always get enough volume at idle or cranking to produce the pressure, but under load, as the volume falls off, so does the pressure.
I've only seen this happen on rebuilt units. Even from a reputable builder (who promptly took care of the problem).
When I got the truck back I did notice RTV around the front cover plate but honestly it was everywhere. Will pull the fuel filter in the morning and double check that.
My thought is that with the ICP going to 64.8% and the pressure dropping off lends to your last sentence about volume vs pressure. Is there any other sensor that i need to monitor during a run? Any other sensor that has major contribution to the HPOP system? I have a fuel pressure sensor for my monitor system (edge monitor and sensors) but I haven't programmed that yet which I might tackle tomorrow just to be sure fuel isn't the issue. But I am fairly certain that all is well there. I have high flow banjos, FRX, Oil crossover, and high flow CVD's.
Appreciate your help!! Will get more info tomorrow. Any other sensor to monitor with AE that would be helpful?
If you have one of these tags on your HPOP, remove the HPOP and get an OEM unit, or and upgraded unit from one of the reputable sponsors.
I don't know who makes them but they are bad JuJu, just ask Byron (BBSlider) and for some reason I've been seeing these Reman units in multiple 7.3 and also on Junk yards?
Fuel pressure can cause the same issue. There are screen inside the fuel tank that can become restricted that can cause similar symptoms.
Usually if oil pressure drops off too much, an CEL is set due to low ICP. That can still happen with fuel pressure, but there is no sensor and no corresponding code for fuel issues on these trucks.
07-15-2017, 04:15 PM
