moostang

Upon start up , i'm hearing a thumping noise coming from what seems like under the steering column.. to the right side where your right calf would be.

Any clue ?? It goes away after about a minute.

The noise seems violent.



Thanks,

Patrick

guofan

Dude, I have the same popping sound too. To me it comes from the center air vents. It doesn't go away for me. Maybe it doesn't go away for you either, because your music will overpower that sound.

ANYONE KNOW WTF is causing it?

M-bENZ

what kind of sound is that ? Can you be more specific ?

Andy

Mka77

You might to make a trip to a shop. Mike

guofan

It sounds like a low sudden popping thump. lol hard to describe dude. It's f ing annoying.

M-bENZ

ahahah but it came from where ? under the engine bay ? I mean where ?

Andy

guofan

Well, mine sounded like behind the center air vents, above the radio. Maybe its too freaking powerful, needs extra holes to release some power. hahaha

coin

Almost positive it's the stepper motor. It's a very common issue in W203.

W203 Stepper Motor DIY

mikare

I got a different noise. It is from the shield under the wiper. When I drive on the bumpy road, it sounds like a bird hiding in my car.
I went to the dealer they fix it, but now the sound show up again, but only on the specific kind of bumpy road.

moostang

Talking to my indy mechanic ( family friend ) just from telephone diagnosing , he narrowed it down to the flapper vacuum thing isn't keeping the suction thus causing my thumping sound upon start up. As of now, the a/c still works ... and fortunantly, i still have my warranty. Off to the dealer I go. I'll definitely keep you guys updated on what is up
-Patrick

Mka77

All that angst and worrying what it might be, and all the while the car is still under warranty. That would have been my first call, and visit. If it wasn't a covered item you could have gotten the diagnosed problem and then got the exact answer you were looking for from lots of resident experts here, of which i am not one of. I hope your issue is resolved under warranty. Good luck with it, Mike

guofan

That DIY is nuts man, I can't do it myself lol