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BMW 730d Injector Copper Seal Leak — Diesel in Oil — BMW 7 Series 2002 | MyCarFault

BMW 730d Injector Copper Seal Leak — Diesel in Oil

BMW 7 Series 2002 M57N/M57N2 3.0d

Safe to Drive?

✅ Safe to Drive

Urgency Level

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The copper sealing washers on M57 injectors degrade over time, allowing combustion gases and diesel to pass the injector bore into the rocker cover area. Symptoms include diesel smell in cabin, oily or sooty residue around injector bases, and oil level rising due to diesel dilution. Continuing to drive causes rapid bearing damage from diluted oil.

Repair / Solution

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