viper1996

My 03 runs great but on idle it has a cycling sound like a washing machine...it is not that bad but curious as to what it could be...Thanks

Rudeney

Is it an actual noise or a "feeling"? Maybe bad motor mounts?

viper1996

I did replace the motor mounts, one was collapsed...You can feel it and hear it...Off idle its fine...It is slight but noticeable...Thanks...

fooschnickens

Did you check the trans mount as well? Usually a good idea to go ahead and do both at the same time as one failing will wear out the other that much faster.

Rudeney

Did it just recently get very hot where you live? I've always found that MBZ engines just don't like extremely hot and humid weather. My SL550 idles jsut a bit less smoothly in the summer, as did my CLK550's. I had an ML320 that absolutely hated hot/humid weather - it would sometime even die at idle. Neither I not the dealer ever found out what caused it as everything was "normal and in spec" until ti would die.

viper1996

Def not the heat....gonna take a look at the tranny mount...

fooschnickens

You can also do the old broomstick test and see if it's any of the accessories that are grinding or part of the engine itself. I know on my W210 the tensioner pulley was a bit of a weak point, but that usually squeaked rather than the chugging sound you're describing.

Noir230

Have you had the noise all along? If so, it may be normal supercharger noise. They're quite noisy. I took my car to a MB-only indy when I first got it who told me it's normal. ** Sorry, I just assumed your car is an AMG and I just noticed it doesn't say which model you have.** Never mind.

viper1996

Ha, Wish I had a blower to be noisy...Car sounds fine when listening under the hood...So I think the tranny mount is the culprit...After I check I will post findings...

makterna

My M113 engine has a valve ticking noise which can only be heard at certain RPMs. According to other threads, it is old oil/carbon deposits on the valve/valve seats. Some say changing the oil to Mobil 1 fixes it, but in my case there was no difference.

If this is true, how do we get rid of those deposits? I recently did a CataClean, which worked and fixed my check engine light by cleaning the cats from soot deposits. Not sure if it is supposed to fix valve tick too but anyhow, it didnt, at least not in my case.