HELLO ALL. NEW DUDE HERE. I'VE GOT A 2013 C63 @ 78K MILES, WITH NOTHING MODDED ASIDE FORM A RES DELETE. I'VE REPLACED PLUGS, AND INJECTORS CHASING DOWN THIS WEIRD PINGING NOISE I GET WHEN CRUISING AT LOW RPM IN HIGH GEAR HIGHWAY SPEED. ILL APPLY THROTTLE LIGHTLY AND GET THE PING. IS SOUNDS LIKE A BAD OR LOW QUALITY GAS PING. I'VE RUN HIGHTEST, 100OCT AND BOOSTERS TO TEST. NOTHING SEEMS TO FIX IT. HAPPENS IN EITHER TRANS SETTING, HIGHWAY SPEED, LIGHT THROTTLE APPLICATION. ANYONE HAVE ANY CLUE? NO CHECK ENGINE LIGHTS, PASSES ALL MISFIRE CHECKS, ALL MONITORS ARE PASSED.

 

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