Medium and Heavy Trucks
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Hi my name is***** will be glad to help. Try unplugging the ICP sensor to see if possibly the engine will run in default ECM settings. If not then other potential causes are Cam sensor ( Loss of speed signal to the ECM) , Sticking IPR valve, Fuel supply problems. Let me know
Thanks for the update. Yes a faulty IDM or IDM relay could cause the problem.... Will it fire off of ether?
Here is the Cam sensor test. Low cranking RPM can cause problems as well
Most shops use a known good IDM to swap for test purposes but unfortunately this is not always an option for most people. So the ICP pressure never drops off when checked with a mechanical gauge?
It is extremely high voltage enough to kill a person and I do not recommend playing with that.
Injector Drive Module Service Tips
IMPORTANTRead Before Injector Drive Module Replacement or TroubleshootingThe Injector Drive Module (IDM), responds to commands from the PCM, steps up the vehicle 12V power to 115V, supplies the 115V to activate the injectors and monitors faults in the IDM and injector electrical circuits.IDM codes can indicate a problem with the IDM and/or injector electrical circuits. IDM codes can also be set by problems elsewhere in the engine.IDM codes are stored in one of the three tests:• Key on engine off (KOEO).• Continuous memory codes.• Injector electrical buzz test.The only way to clear IDM codes is to clear the continuous codes.The use of an appropriate scan tool is required to properly diagnose IDM and injector related problems.Basic Diagnostic StepsWhen IDM diagnostic codes (DTC) are present follow the following steps:1. Record all codes in the key on engine off test (KOEO) and injector electrical buzz test.2. Record and then clear the continuous codes.3. Run the KOEO and injector electrical buzz tests.4. IDM codes that reappear are hard faults.5. If no codes reappear then the fault is intermittent.6. Troubleshoot the codes.
Hi, did you get this resolved?
If the fuel system and pressure checks good then I would start by pressurizing the high pressure rail to check for leaks in the injector o rings etc. Pressure test the cooling system for a leaking injector cup.... Also if the injector o rings test ok you could have a weak injector. Just make sure the compression in the cylinders are all in line with each other. Unless there is something dramatic like a head gasket or ring issue on one cylinder I doubt this will be your cause.
Hi, Did you get this resolved?
Hi, Did you still need help with this?
Thank you for the update. Yes I believe you have. Try it with some oil in those cylinders and if it comes up it means rings/piston. If it stays about the same it will be head/head gasket
Your cylinders around 400 PSI are within normal expected range. When you start getting below 375, 350, etc your engine is tired. 250PSI on a couple of cylinders indicates a problem in those cylinders. Rings, valves, head gasket, etc
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