Hello, any help would be greatly appreciated.

My 2000 C280 has been stalling out on me. I've had the car for roughly 3 years and 55k miles and drive around for my job. I haven't had any fuel system problems in my ownership of the vehicle but roughly two weeks ago once I had driven most of the day, I turned the car off and did not attempt to restart the car for roughly 30 minutes at which point the car would crank but would not start. After several attempts and about 10 minutes I was able to restart the car. This only happened 1-2 times a week between incidents. At this point I was thinking the fuel filter was going out. So I bought a new filter to change out. I had not found the time to change the filter and then on the road again it happened again where I drove fine for hours and turned off the car and let it sit for 30 minutes and attempted to restart where it cranks but does not start. This lasted for 15 minutes and started again and I drove home which was roughly an hour and a half of driving. Once home I had planned to replace the filter but had a water problem from my A/C system in the house and had to rush to the hardware store.

So on my way to the store which is roughly 5 miles away, (remember I drove hours earlier) it stalled out during driving where I pulled over and restarted it, and drove off but almost immediately the car cut off again. Then it would not restart no matter how many times I cranked it. Luckily I had tools and the filter in the trunk just in case. So I replaced the filter and was on my way.

The old filter was so clogged that you couldn't even blow through it. So the next day I go to drive the car, drive for an hour or so and bamm, car won't restart after driving for 30 minutes or so. At this point it will start after 30 minutes but will cut out randomly.

So then I assumed that the fuel pump was failing due to the clogged filter. My thoughts were that since the filter was clogged, the pump was pumping harder and strained/damaged the pump. I ordered a replacement pump from Autozone and replaced it yesterday.

This morning I start the car no problems, drive for less than 15 minutes to my office and it sat for a couple hours. I then drove the car for another 15 minutes and turned it off and it won't start, again.

After sitting for 30-45 minutes it started no problem and let me drive for roughly 20 minutes again before cutting out, luckily in my driveway this time.

So now my thoughts are that the fuel pump relay is failing due to the failing pump which was drawing more volts due to the clogged filter. Has anyone else experienced this or come across it in the forums??

I am going to pick up a new relay from the dealer tomorrow and see it that solves the problem but wanted to try and get some advice from the MB community. Again any advice would be greatly appreciated. Thanks.

 

Sounds like classic signs of a problem with the CPS, crankshaft position sensor. Lots of these are going out now due to age. Do some searching and you will find lots of posts about this. It sounds like you are a DIY guy, so you should be able to do this yourself and save $$. Try autohausaz or buymbparts for decent prices and free shipping over $50.

 

Thanks for the advice! I replaced the CPS and no problems thus far. Yea I would of looked to buy the CPS online but I needed the car functioning before Monday so I headed up to my locale MB dealer which had it in stock. It cost me to get it that day, $158 for the sensor, and ten bucks in gas but it was a good day for a couple hour bike ride! Thanks again for the advice.