I have a lack of power under full accelleration. This is on a 2006 E55. There are no error messages or check engine lights on to indicate a problem, and the car drives 100% normally, except it feels like it is missing about 100-150 horsepower. There are no noises or anything strange at all. These cars are supposed to be lightning fast and it is just kinda strong under full throttle, what I would expect from a 4.3 liter motor. This will be the first problem like this I have explored with a mercedes, and am not too familiar with how mercedes sets up their supercharger. I see a clutch on the front of it and thought maybe it was not engaging, but i dont know how to test that either. I have not yet scanned codes, but I do have a very capable aftermarket scanner that i intend to use tomorrow to see if there are any codes that would not turn the check engine light on. Thanks for the help!!
Country: United StatesMake: Mercedes-BenzModel: e55 amgYear: 2006
nothing really. spun s/c with engine off by hand, spun smoothly, with light resistance
What happens often is a fault code for the intake air temperature is too high and this turns off the supercharger.
The supercharger clutch is not engaged at idle or in park/neutral either.
You can usually here the clutch actuate when giving it a little bit of gas in drive around the 1500-2000 rpm area. It should sound almost like a chirp.
Anyways, what causes the air intake temp too high fault code is a failure of the intercooler/low temp circuit water pump.
ok great..i wonder why that wouldnt turn on the check engine light?? so if i do indeed find a fault code for the iat sensor, should i just replace that?
No, its usually not the iat sensor, but the intercooler water pump. For some reason, this code does not always trip the check engine light.
ok sorry only about half of your first chat session came through first.
where is the intercooler water pump located and how difficult a repair is it?
It's on the passenger side, just in behind the bumper. Just remove the front engine under shield. There is just 1 10 mm bolt holding it. There are 2 coolant hoses going to it. The fuse usually blows too but I'm not sure which one it is. The fuse chart on the side of the dash on the drivers side should tell you.
Mercedes-Benz Master Certified technician
ok great thanks very much. ill accept for now, check in the morning, and let u know if i have any other questions or issues..
actually do u happen to know about how much it costs?
I think dealer list is $900-1000 Unfortunately. Just apply power to it and see if it pumpsSometimes removing them jiggles them around and they start working temporarily. It really is a common problem. Renntech does sell an upgraded one for $1500 I think.
I found list to be 387, but I got one thru carquest for 130, and its still a Bosch pump, and identical to the stock unit...I found that this seems to be a very common issue..thanks again for thevhelp