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Hello, what can I help you wiht?
Ok, so the injector failed a buzz test on the same cylinder regardless of swapping injectors, new harness and still failed a buzz test.What kind of trouble codes did you get is any before replacing any parts? Base compression is good?Blue smoke,white or gray?It ran with the new pcm, you had it programmed to the vehicle?
All the injectors are enegrized during the buzz test and it spikes each one as it tests its operation so its not unusal to hear them buzz long as they are not buzzing at the same pitch at the same time.
Ok and what color was the smoke, fuel, oil, or water? Not unusal for a valve cover harness to fail or cause a bad connection.Youhave communication with the new pcm and no codes now>
Ok so its dumping too much fuel into the number 6 cylinder regardless from what you are saying. Will it run with the old IDM?
What prompted the pcm repleacment and was it reprogrammed to the truck, new pcms come blank and need to be reflashed
Ok Im just concerned right now with it not running at all first with the pcm/idm swap. Its a direct injection system so once the injector is in the cylinder it shouldnt dump fuel until it is commanded to by pcm & idm and of course high pressure oil system control. And being so its a high voltage dc system when you mention having 5 volts at the injectors? not the type of system you backprobe with a voltmeter or are you talking about checking the circuit at the idm?
Ok, thats just during the buzz cycle test using the scan tool. Firstthing you need to do is get it running again so I would look into putting the original PCM and IDM back in to do further testing. Run Cylinder contribution test and cancel injectors to check operation.
Ok, then you might be loosing IPC. You said it was over 500 when it starts, does it drop off when it wont restart? Issue with the IPR regulating oil pressure. Is the high pressure oil resouivoir full of oil
Ok is ipr readin approx 85 %
The forward one should be for the glow plug, they tend to melt when they fail ,the fuel heater is located under the fuel seperator bowl.this pic is the glow plug relay
the other solenoid powers the heater yes. i dont see any blue wire comin off either relay in the schematic
Wont let me post the wiring diagram, brown and yellow go to the glow plugs brown one bank, yellow the other.Black/orange hot all times. Red wire and a purple orange wire run off to control
Hmm, only a solid red wire goes to either the glow plug and fuel heater relay.I listed the color of wires to the glow plug relay. The fuel heater relay are Black orange/power supply. red, and violet. the fuel relay only uses 3 wires
Purple orange on the glow plug relay is the signal wire from the pcm to ground the energized side of the relay and close the relay and send power to the glow plugs
Ok good.If you run a cylnder contribution test does it show any faults besides just checking for memory codes? No codes running a KOER test?
Its odd for it to keep comingback to the number 6 cylinder if the injector is good, not setting codes. Fuel supply runs though the head and then into the cylinder through the injector and seaed by the injector cup. All you can do is check for a supply system leakdown with the engine offl\. but since it only does it when running and appears to be isolated to one cylinder, either a control or wiring issue of mechanical fault.
Im just surprised its not setting any codes whatsoever, no problem with ebp, baro,ipr or ipc. cam sensor/rpm issues. Passes a cylinder contribution test and key on engine running test. But it will still flag cylinder 6 on buzz test only?
Ok and new harness inside the valve cover so only thing that could trip same injector fault would be the wiring between the idm module and the injector.Since thats what governs how the injector fires and for how long. Try overlaying the one circuit between both with your own wiring and see if the code clears.All the major parts are flow testing correctly. Other than a cam sensor shutting the engine down and a loss of rpm signal an no restart
I gotcha, double check it by seeing if it can carry a load by lighting a bulb and wiggling the harness. If it cant light a bulb it is a weak circuit.