HELLO TO ALL. 08 S63 HERE,... SAY I JUST HAD MY MB TO CHANGE MY OIL , THEN ABOUT A FEW DAYS LATER I STRAT HEARING A TAPPING NOICE COMING FROM ENGINE COMPARTMENT . WHEN I REB UP, IT SPEEDS UP AND DOWN

cold engine? you know it takes that beast a while to get to 172 F

Sounds like a stuck hydraulic lifter...it may be that they put some cheap crap oil in there and it has a lifter stuck....miobil 1 is the only way to go and sometimes Quick change places dont use the good stuff...just a guess on my part. MB dealer should use the good stuff.

what is the fix mrbenzes?

Go have the oil check for level and possibly change with correct weight oil

Verify that the noise is actually coming from engine and not an accessary or pulley.

I agree with bozapp, you may have to do another oil change and ensure they use Mobil 1 5W-30 oil...then drive for a while on the interstate to flush the lifters thoroughly. Sometimes it may take a removal and cleaning of the lifters which is a HUGE job...
Mike

+1 on oil change. I had a tapping noise too, didn't think too much of it since it goes away after 5mins. Once I changed oil (9 quarts of M1 0w-40) went away completely on cold start.

and what is the weight of the oil going to do?

the lower the viscosity number, the thinner the oil...a "0" in 0w30 means the oil is very thin when warm and can flow better through the lifters and not clog. Clogged lifters dont hold pressure against the rockers and you get the "Clicking" sound when the cam slaps the rocker against the valve.
Mike

the lower the viscosity number, the thinner the oil...a "0" in 0w30 means the oil is very thin when warm and can flow better through the lifters and not clog. Clogged lifters dont hold pressure against the rockers and you get the "Clicking" sound when the cam slaps the rocker against the valve.
Mike

Thank you mr. Benzes I couldn't have pu.t it better myself.

Thank you, then 0W30 or 0W40 Mobile 1 may be my next oil change because I too get that every now and then.