replacing the fuel pump on the c280 - PeachParts Mercedes-Benz Forum

msethk · #1 08-24-2009, 05:40 PM

I travelled from Tucson to Laughlin NV a few weeks ago in the mercedes... (man was it hot there, 128 degrees???) The car ran fine on the way up and while I was there. My tank was low, around 1/4 the day before I left and on a short drive back to the hotel from the casino the car died. I waited a few minutes and it started and then died again after about 2 minutes. Once again after waiting a few minute it started and ran long enough for me to get it a few blocks to a gas station. ( my concern was that the fuel pump is weak and was running too warm.) When I pulled up to the pump I could hear a noise that sounded like a rough running pump from the right rear fenderwell area. I filled the car with fuel and it ran fine. I drove the next day back to Tucson, while being careful to keep the tank at at least half-full, with no problems. When I was just a few miles from home the car really began to run rough, I kept the car just over 1000 rpm's at stop signs to keep it running. After it sat on the driveway for an hour or so i started it to put it into the garage and it seemed to idle ok. I have replaced the OVP on the car within the past 24 months, and there is no check engine light on. The harness has NOT been replaced but in this situation I would rather start with the cheaper parts to try to solve the problem. Does anyone have any other ideas or does the culprit sound like the fuel pump? I have singled it out due to the noise it was making when I pulled into the gas station.

Also, does anyone have a link to the procedure of changing it out??? didnt see anything here on the site.

Thanks

mbdoc · #2 08-25-2009, 08:23 AM

Simple job under the car, remove a plastic cover & unbolt pump.

Make sure to squeeze off the fuel feed line from the tank.

Could you have gotten some "bad" fuel?

msethk · #3 08-25-2009, 04:11 PM

the fuel was from shell and ran good the entire way up on the trip. the car has had just a little sputter under real hard acceleration for some time but not enough to bother me (and barely noticable.) Is the pump in the fenderwell or at an easy location to get to?? I looked for a thread to the procedure list but couldnt find anything...

i did call my old indie in Omaha who is a fantastic mechanic but that doesnt help me here and he said check harness, egr, or pump but sounded convinced it may be the pump after i told him about the noises I heard before adding fuel

btw: thanks for the response