Cranking - No start questions / Confusion

[cdelap]

To start I will give you the history of the events that lead up to the no-start

2 weeks ago, I was driving home and as I merged onto the freeway as my ICP hit 1900psi the engine stumbled and would not build more than 800psi I drove the next 3 miles home with limited power but still enough to get into the driveway. let her sit overnight and went out and retrieved codes the only code was a 2290 Low ICP. I cleared the code and she started right up.

I drove the truck for 3 more days with no problems until she went into a Cranking --No start and only 230psi showing for the ICP, I pulled the wires to the sensor where it showed 730psi and still nothing. due to getting engaged and work I had to let her sit for almost a week till I took her into a friends shop where he started looking at the PIDS through IDS it showed a ICP of 1800 and we went on to test and diagnose that the no-start was related to the glow-plug relays (something I would have expected on a 7.3)

So the truck is back on the road now and has stumbled a couple times once dropping ICP down to 400 and set a 0069 MAP sensor / BAR sensor correlation error.

The truck drives well and seems to be operating correct for now.

So my question is: is there a correlation between the MAP / BAR sensor and ICP, the ICP was tested and is operating properly.

As for as further Diagnostics what is my next step, I am currently logging any PIDs so that I can review them if it stumbles again

As always thanks for the help!!!

[05 Pstroker]

Can't answer the question below.

(So my question is: is there a correlation between the MAP / BAR sensor and ICP, the ICP was tested and is operating properly.)

But did you get a code with the no start issue (2285 maybe).

The reason I ask is that I had the no start issue this summer which lasted for about 45 minutes. The truck started back up and ran normal till Saturday before last and did it again and showed a 2285 trouble code. ICP reading while cranking was at 125#s. Had it towed home and tried cranking every so often and ICP pressure rose gradually and reached 350 before I had another vehicle to go and purchase an ICP sensor. Changed the sensor and the truck fired right up. Hope this might help.

[cdelap]

no 2285 code. I have tested to make sure the ICP Sensor is not bias and it seems to function correct.

[05 Pstroker]

Good deal. Only reason I mentioned it was that has been the only easy/cheap fix I have had in years. Good luck.

[twoicebergs]

So my question is: is there a correlation between the MAP / BAR sensor and ICP, the ICP was tested and is operating properly.

As for as further Diagnostics what is my next step, I am currently logging any PIDs so that I can review them if it stumbles again

No, not directly. The MAP and BP are used by the PCM to control fuel quantity, timing and control, and VGT (plus a few other functions). However, from the 6.0l Powerstroke Manual 2003.25 page 115,

• The primary function of the ICP sensor is to provide a feedback signal to the PCM indicating ICP.
• The PCM monitors ICP as the engine is operating to modulate the IPR. This is a closed loop function which means the PCM continously monitors and adjusts for ideal ICP determined by conditions such as load, speed, and temperature.
• The PCM monitors the ICP signal to determine if the performance of the hydraulic system is satisfactory.
• During engine operation, if the PCM recognizes that the ICP signal is lower or higher than the value the IPR is trying to achieve the PCM will set a Diagnostic Trouble Code (DTC) [2290] and illuminate the amber malfunction indicator lamp on the dash.
• The ICP signal from the PCM is one of the signals the FICM uses to command the correct injection timing.
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The MAF sensor outputs an analog voltage signal to the PCM proportional to the air mass. This directly affects the commanded IPR position. As well, the AP (Accelerator Pedal) has a major affect on the commanded IPR position from a PCM signal.

You next step is to see what the IPR is doing when the problems are happening. The code 2290 is a maintenance trigger to look at the HPO system for a leak. It is possible you are in the early/intermittent stage of a HPO problem.