Hi guys. New e55 amg owner. drastic power loss after few hard starts. Mainly noticable after going 50-60 mph. No power. Crawls up speedo. Fine from start. Only hear supercharger chirp now and again? Is this normal or means my s\charger is not working properly all the time. Secondly I use a particular stretch of road (hill) to time how fast a car is. Twice I have done this run and whilst still on the hill ( not extremely steep) my car stops going at 115mph and rev counter on 5500rpm. No downshift\upshift or further power after this point. Like engine has frozen at this particular point. done 130+ on straight and just to confirm no speed limiters are on. (cruise stalk or winter tyre settings). Bit pi***d off as just had the car 1 week. MB dealer sold it to me and replaced the v kompressor belt before giving the car to me. Help pls. Car booked into dealer on friday but some advice would be greatly appreciated.

The most common problem E55's have is the intercooler pump. NOT the water pump, it's the intercooler pump. Very common failure that will not throw ANY engine lights or codes. If the car has never had the intercooler pump replaced, do not leave that dealer without having that done!!!

They may fight you, but I would really push to have it replaced. Story after story on this forum of these going bad and cars acting like slugs.

I have a 03' also and had the same problem with mine. I just had the I/C pump replaced and the problem seems to be fixed for now. Have them check the service records to see if it has ever been replaced, I think there was a recall on that pump a few years ago. I found out mine had never been replaced, and my dealer had no problem replacing it. Good luck. Also do not let them flash your ECU, they do this to cut the power by about 60 hp. Good luck!!


Also try resetting the ECU, see link below:

https://mbworld.org/forums/w211-amg/148019-holy-crap-you-guys-sneaky-ecu-reset-works.html

Do a search here for IC pump.