Squeeling Birds Under The Hood!
 

I have a 1993 190e 2.6 (104,000 mi). About 6 months ago I had to have the water pump replaced. The job cost me about $900 (complete w/ new mercedes waterpump, did I get ripped off?). Shortly after that, I started hearing a squeal after starting the car, especially on cold mornings (50 degrees F and below). The squealing stops as I accelerate and a few minutes later the noise dissappears. As time has gone on, the squealing doesn't go away so quickly and now there is a constant chirping sound when the car idles. The affable service tech at the Mercedes repair shop (the smae that did the water pump) says it's the air pump. An $800 part. AGGGGHHHH! However, the service manger also said that the air pump could simply be dissconnected. Is that true? If so, can you tell me how to dissconnect it. I've also heard dissconnection will result in the service engine light coming on. Is there an overide for this? Please help.

I did the water pump on my 300E 2.6 in about 5 hours and the parts (with new MBZ pump) were about $100. So if that's all your mechanic did, $900 is pretty pricey.

You might get a second or even a third opinion on the squeal. Sounds to me like it could be the belt adjustment since it started after changing your water pump.

Does your state require a smog certificate? If so, disconnecting the pump is illegal. If you really need to replace the pump, you might look around for a used one. Since it's smog related, I would encourage you to fix the problem correctly.

Sounds like a loose / improperly tightened belt to me, the tech may have left some oil/grease on it after replacing the pump...

Just my thoughts!!

Sounds to me like you need a new tech. A water pump shouldn't cost more than half what you paid.

It could be a loose belt. However, if it is the air pump, they can be had for around $300-$400 for a rebuilt one. I think it's about two hours labor to put one on, or it's not too hard to do yourself.

I just had mine replaced on a 300SE, it cost me $350 installed.