petez1125

I have a 2005 C55 with 75 K on it. This morning I got my car washed, not sure if that has anything to do with my problem or not. When I got to work and turned my car off I hear a pump running. I was hoping it was coming from the car next to me but once I popped my hood I found it was my car. It sounded like the noise was coming from the front of the engine, maybe under the engine cover.

I waited 5 mins looking around and the sound was not as loud as when I first parked, however it was still there. I went into the office to research what this might be. From reading some posts on C32's and couple C55's it looks like perhaps it is the Secondary Air pump and the relay might be the problem. I then went back outside to try and pull a fuse hoping that I could save the pump from burning up. When I got to my car there was no more sound. I turned it on and got no CEL, but I am not sure if the pump is fried or not. I guess when I take the car out to get lunch I will find out.

Has anyone else had this happen? How much am I looking at for a repair? Also, this had to happen on my Birthday? I should have driven the C230 today!!!

Thanks
Pete

Quicktwinturbo

I think it's normal.. They usually turns on when you start the car in cold weather.
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petez1125

I agree with it turning on when I first start the car, but it was running when the car was turned OFF.

I have never heard anything running before when I powered the car off. The sound was loud at first, like I have a supercharger under there. It gradly died down, perhaps as the pump was burning up?

petez1125

Has no one else experienced this problem?

wawy

To me, this sounds like the issue I had on my old C32 whereby the issue was actually the secondary air pump.....

Zeppelin

I agree with the Sec Air Pump. You can see if the pump will run with just it plugged in the to battery. You can also pull the relay and pull the plastic cover off it to see if the contacts are melted.

arekux

just unplug the sec. air pump, u dont need it, just plug it in when u do smog on ur car, because it will trow a cel, its better to unplug it so it doesnt fail, because they are usually expensive, only need it for emissions. They usually go for $400-600 new, and $150-200 used, for c32 i dunno if its less for c55s.