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Engine Noise Diagnosis





ENGINE KNOCK NOISE (FUEL KNOCK)





INTERMITTENT NOISE ON IDLE ONLY, DISAPPEARING WHEN ENGINE SPEED IS INCREASED





NOISE AT SLOW IDLE OR WITH HOT OIL; QUIET AT HIGHER ENGINE SPEEDS OR WITH COLD OIL





NOISE AT HIGH VEHICLE SPEEDS, QUIET AT LOW VEHICLE SPEEDS





NOISE REGARDLESS OF ENGINE SPEED





VALVE TRAIN NOISE





VIBRATING OR RATTLING FROM EXHAUST SYSTEM





EXHAUST LEAKAGE AND/OR NOISE