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Intermittent Power Loss - ICP Desired 2800psi @ WOT
So I have been troubleshooting an 2005 ambulance with 139kmi for a customer of mine and have come across an issue that I have not been able to find discussed anywhere and I have never seen before. The ambulance will have an intermittent loss of power when hot and trying to accelerate from a stop. During this power loss the ICP desired will not increase past 2800psi and 7psi boost. ICP Actual is right there with it and IPR is at 40 something %. There are no codes thrown, and if stop and accelerate again the ambulance will accelerate away at 3800psi and 19psi boost. I have also checked the following:
-EGR Removed and cleaned
-New Turbo and VGT Selenoid
-EBP tube and sensor cleaned - 14.7psi at idle, WOT in park 38psi
-CMP and CKP seem to stay synced. Swapped CMP with known good.
-Check Accelerator pedal position - Appears Accurate.
-Check and Monitor FICM voltage and sync. Never lower than 47 volts.
-System voltage while problem occurs 13.9volts
-Fuel pressure at idle 55psi, WOT 52psi, During loss of power 52psi.
-Checked ICP plug, no sign of oil. No indication of biased sensor.
-Plugs and Pigtails all look fine on CMP,CKP, FICM, VGT, EGR, EBP, IPR, ICP
-EOT and ECT are showing 1-3deg delta
-Ran 2 bottles of REV-X
-New Fuel Filters - No fuel in water
-2000miles into an oil change
-Passes Buzz test, and contribution test. I deactivated each injector at idle and saw consistent power loss with each injector.
-Passes KOEO and KOER tests with no faults found.
-Fuel suction is at like 2inHG when check at fuel pump
It seems to me like it is not a HPOP or Fuel issue. Starts great hot or cold and low ICP will be followed immediately by normal ICP readings. It seems to me that the the load and therefore the desired ICP is being calculated wrong by the PCM for some reason. Like i said it sets the desired ICP at around 2800psi even though the rig is at 30mph, 6psi boost, and WOT.
I am looking for any ideas to go after and wondering if anyone has ever seen anything like this before. I appreciate all help and ideas, especially from any of the ford techs that might like to pitch in.
Thanks in advance