Engine Noise - Normal or Issue?
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E63S Estate
Engine Noise - Normal or Issue?
Hi all - My recently acquired G55K is concerning me with some engine sounds. Under acceleration, the exhaust noise begins to sound "airy" and unlike the exhaust under idle, or revving in neutral. Also, in neutral, the engine has a sound like marbles clinking together, which may just be normal valvetrain noise. I wanted to see if your trained ears might suspect anything gone awry. Last owner just completed an oil change and serviced coils/spark plugs in January 2025.
I don't think it's lifter noise as I recently resolved that using the Liqui Moly hydraulic lifter additive - awesome stuff! Not sure if the sound below under load suggests lost compression/cylinder scoring/blowby, or if it's just normal. With the recent oil change from the last seller a week ago, I haven't noticed any oil consumption, and under hard acceleration, I don't see any smoke. Might be an exhaust leak, though crawling around underneath didn't yield anything obvious.
Here are some youtube shorts with the sound:
Acceleration Noise:
Idle Noise:
Thanks for any feedback you might have. A local shop quoted me $850 for a compression/leakdown test, so I just wanted to check here before doing that.
I don't think it's lifter noise as I recently resolved that using the Liqui Moly hydraulic lifter additive - awesome stuff! Not sure if the sound below under load suggests lost compression/cylinder scoring/blowby, or if it's just normal. With the recent oil change from the last seller a week ago, I haven't noticed any oil consumption, and under hard acceleration, I don't see any smoke. Might be an exhaust leak, though crawling around underneath didn't yield anything obvious.
Here are some youtube shorts with the sound:
Acceleration Noise:
Thanks for any feedback you might have. A local shop quoted me $850 for a compression/leakdown test, so I just wanted to check here before doing that.
