Hi I was wondering if anyone know what this is or has the samee thing going on as well. Every time I go to warm up my car I hear this sound coming out of the engine. It sounds like as if you were vacuuming your rug then later it goes away. Does anyone know what this sound is and if its normal?Thanks in advance

 

My '02 C240 does this, and has since day one. The dealer told me once the exact bit that makes the noise when I asked about it, but I forget. The gist was that it's a normal part of cold start operation - something to do with the emissions system. Sorry to be vague; it's been over 5 years since I asked about it, and I don't remember the details.

 

Thanks Brian for the replie back. I feel alot better knowing I'm not the only one with this sound must be normal and thanks again.

 

its the sound of the mice waking up, taking showers, making coffee and getting on the wheel...

 

or the gerbils

mine doesn't do it, i can't relate sorry

 

My mice still owe me last month's rent.

haha, but yeah, I noticed the same thing. I started my car the other night, and stood outside of it and heard the noise, but it went away like after two minutes. Pretty cold out.

 

Air injection pump

 

M111 sound worse...

 

no, i havne't had this problem.

 

ive had this. but it kinda sounds cool with my exhaust =D