On another thread I'm having stalling trouble, just posted this thread to get a quick answer and maybe help someone else performing a search in the future.

Will the following throw an engine trouble code most if not every time it happens? Just got the AE in and no 'real' codes were found.

ICP failure?
IPR Failure?
Fuel pump intermittent failure?

Thanks.

 

My ICP sensor was leaking oil out through the electrical connectors. There was no code retrieved by my AE scan tool for that particular issue. However, even though my ICP was leaking, it just have been working still because my Injector Control Pressure was about 485 psi at idle. I think if the ICP sensor fails, there is some default value used which yields about 750 psi at idle. However, I am not entirely sure about this. I just got my AE and still learning myself....

 

Thanks for the speedy reply. I'm fairly new to diesels myself, got my 02 in 08 and my AE last night. I've learned that I have a lot to learn. ;-)

 

ICP sensor failures or wiring harness failures typically throw codes. Not all the time, but most of the time.

If you have a problem with the IPR, it's often very difficult for it to throw a code. For example, when I had my stock HPOP I had a failing IPR that would randomly cause the engine to stall. No codes, no nothing, just stall. The reason it wouldn't throw codes is the PCM is set to see low or high pressure after several seconds, not immediately. So when the IPR suddenly decides to spaz out and instantly stall the truck, the PCM has not seen a low/high oil condition long enough to trigger a code.

With the fuel pump, the PCM does very little with that. Unless you have an electrical short, the PCM won't throw a code for the fuel pump. Most of the time a dying fuel pump is diagnosed with a fuel pressure gauge hooked to the test port on the back of the fuel bowl, or just by hearing it make horrible noises.

 

Thank you the explanation. I didn't know the IPR problem had to be in for a specified time. I'm learning.

Wasn't sure about the fuel pump, the AE gave the options to read some inputs but didn't give any results and the truck was running. That's first thing on my list when I get home tonight.

 

Thank you Curtis, very helpful infomation.