Hi i am new to the forums and i am in desperate need, sorry if i had posted this thread at the wrong location.

I own a W211 2003 E500 Sport Sedan with 145k miles

My car all of a sudden doesn't start anymore. Before we assume anything. I know for fact it is not the Cam Shaft Sensor or Crank Shaft Sensor because i have already changed them before my car stopped working. I have checked my fuel pump and they seem/look fine to me (Not to sure what to look for though). I am the second owner for this car and i remember before i bought this car i had 3 codes which were gear ratio, mass air flow, and O2 sensor. I don't know remember the exact code but i can always check again. I had an exhaust leak that i fixed already. My transmission has been slipping because of the gear ratio, so i did a ATF change. I am not sure if transmission slipping has anything to do with the car not starting but i just wanted to inform you guys as much details as possible.

Well basically i was driving from my house to Gary to pick up a E63 bumper which was like a 30 mile drive. On the way there my car was smooth had no problems but on the way back the car felt weird/different. Like when i press the gas pedal it felt kinda laggy like i was pressing the gas pedal but it didn't want to go. The only way the car went is if i press the gas pedal further almost like flooring it. I drove to a restaurant to grab some lunch which was like a 45 minute gap. Then when i went back to my car and cranked it, the car started but the car was shaking pretty crazy. I never felt it shake like that before and all of a sudden it shut down on me. I started the car again and it still shook but this time it the car shut down immediately. After that my car never started anymore. It would crank but it wouldn't start so i had to tow it.

I know it is not the Cam Shaft Sensor, Crank Shaft Sensor, Battery, Starter, Alternator, or fuel pump(Not to sure about fuel pump though)

The last thing i want to do is take it to a dealer

Please help what do you guys think? What should i do?

 

Try a spark plug tester ,to see if its electrical .Then remove the fuel pipe that comes to the fuel distributor. Mind you do it with engine off and keys out. Also wathch out for fuel escaping .Can you here the pump running as you switch it on ?. Then it may be the sensor if you have spark and fuel.

 

Get a star diagnostic done at an indie shop or dealer. In the long run you will save money. Trying to guess what is wrong with a complicated car like your Mercedes cost more time and money.

 

Assume nothing. Just because you installed a CPS doesn't mean it works, connected solidly, and you will have to run codes to find more details.

 

Fuel pump is my guess, again thats a guess. Or you could have a clogged egr valve but that's a far stretch. You wont know anything until you run codes, and still then you may not know. If you know how to use a multimeter, remove your back seat, take the covers off the fuel sending units, check to see that the fuel pump is getting 12 volts during cranking, if in fact they are, your fuel pumps are faulty. Thats one way to rule out a fuel pump. You could take it too a dealer, 1hr checkout fee, buy your parts from a independent dealer and get it done at a indy shop like someone above said. You could also jump your fuel pump relay to make sure its not a fuel pump issue as well.

 

Did you replace the sensors with genuine Bosch parts? Lots of problems with cheapo alternatives.

 

Oh, also, I had a problem like the one you describe when I knocked a vacuum line off the back side of the intake manifold on my old CLK. It was just forward of the MAF. Turns out there were two vacuum connectors there, and I had only plugged one of them back. Once I straightened that out it purred like a kitten.