Hello,
My 1997 C230 whines like an airplane or hair dryer when I start it in the morning. It does seem to go away when the car is warm. The check engine light is on, but the code is EGR valve. It also did this before the check engine light came on, did not seem as bad though.
Any ideas?
Thanks for your time,
Brad

 

Did it just start doing this? It could be your Supercharger.

 

More like a helicopter, right?

My '05 C230K has been making that noise cold for the past 60,000 miles.

The supercharged four cyl. motors were never known for being quiet, and they tell me
that this was one of the main reasons the engine was discontinued for a variety of six cyl. engines.

Just think of yourself as a airline pilot when you drive it. It helps.

 

My neighbor happines to own a 2005 C230 Kompressor Coupe and we where talking about it yesterday when I went out to get my mail. She says the samething about it being loud at start up. Her car only has 30,000 miles on it so I doubt there is something wrong.

 

Hello. I also have a 1997 c230 with a similiar noise. Had it for years. I'm 99% sure it's your air injection pump. When the car is cold the computer reads elevated emission levels so it calls on the air injection pump to push air into the system to reduce the emissions and help with the burn. Once the car warms up it shuts off. I've never had an issue with it except when I went through an exceptionally deep puddle and the pump (which is located on the passenger side bottom of the motor) sucked water in and shorted out (I'm confident thats your noise since it stopped until I repalced it!)) VERY EXPENSIVE if you have MB fix it ($1,100). I found one in a wreck for $150 and it works fine. Took less than 1 hr. to install.