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Had a 6.7 Powerstroke with a weird injector knock that wouldn't show on the scan tool.
Used a mechanic's stethoscope on the high pressure fuel lines, found the knock was loudest at the #3 line fitting. Swapped the injector driver module from another truck and the knock went away. Anyone else had a bad IDM cause a knock that sounded exactly like a mechanical injector?
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emery_brown12d ago
Man, chasing a ghost knock like that is the worst. Spent a whole weekend convinced my 7.3 had a dead injector, turned out to be a loose valve cover gasket letting in just enough air to sound awful. Felt pretty dumb after that one.
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emery_brown12d ago
Tell me about it, I once tore down half an engine chasing a noise that was just a heat shield rattling.
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juliadavis11d ago
Read a forum post where a guy swore his diesel had rod knock. He replaced the main bearings before finding a cracked flex plate, the noise was just echoing through the block. Makes you want to start with the cheap stuff first.
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