Medium and Heavy Trucks
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Hi my name is***** will be glad to help. Check for restrictions or leaks between the tank and pump causing low fuel pressure. Check for low fuel pressure for possible pump or regulator problems. Also check the ICP pressure with a 5000 PSI guage at the ICP sensor port to see if the pressure is around 870 PSI cranking and up to 4000 PSI high idle. If not put 12 V to the IPR to check max HPOP pump pressure. If low with no leaks in the rail or injector o rings the IPR is either sticking or the HPOP is bad. Be sure the IPR is working properly and the ICP sesnor is good
Unplug the ICP sensor and try starting.... This puts the ECm into a default setting to allow the engine to run but it seems you are reading live data for ICP if I am not mistaken through a scan tool? Are you loosing cam/crank sensor signal? Verify that and also see if the IPR may be sticking mechanically
We can post back and forth as needed. I log in periodically throughout the day as needed and will replay back on my next available login. There is additional services by phone if that helps at an added cost or we can continue this way. Have a good night
Hi, It is Dan. I log in periodically throughout the day so feel free to post your follow up messages and I will respond back on my next available logins.
Thanks for the update. Verify your power and grounds to the FICM and if good I would try a test FICM if available or replace yours if power and ground and the harness and relays check good.
Thanks for the update. Here is a diagram that will help to check the harness.
It does have to be programmed but it sounds like maybe you have a loss of power possibly. Check your relays, fuses and IGN power from the switch. You can buy aftermarket programmers as well for these. For axample
Will the relay click at all? I am concerned that your New FICM may have a problem. Is there any warranty with it?
The schematic I posted earlier should be what you are looking for? Let me know