Mystery Noise

[Californian SE]

Hi guys,

Finally I have a roadworthy on the 280SE W108 - but theres one thing bugging me.

When it drives, theres a noise which is almost "ressonated" by the muffler. Its the sound youd get if you blew into a tin whistle and no notes came out, just that sound of whistling air. And its quite loud - very noticable.

To my knowledge it isnt affecting the cars performance, but its very annoying to listen too.

It only happens if the car is rev'd, or when going up through gears (auto) especially up hills. The man who replaced the muffle doesnt know what it is, and the mechanics dont know what it is. Mind you it hasnt seen a Mercedes Dealer yet - for the simple reason Im not a millionaire.

Has anyone else had this problem?? Any info would be greatly appreciated.

Cheers, Luke

[wbain5280]

It sounds like an intake whistle. Check the throttle plate for proper setting, as it it's not used for setting the idle speed.

[mercmad6.3]

Are you 100% sure you don't have an exhaust leak?
Try ,with the engine idling,blocking the exhaust with hand and a cloth .If it's leaking you will soon hear the gas escaping from the holes .

[berfinroy]

If you didn't have the sound before you replace the exhaust system, there isn't much point in looking elsewhere. I'd look for not only an exhaust leak, but also a crimped pipe, and finally I'd have to conclude that the muffler itself may be defective.