Hi All,
This past weekend my car died.
I just wanted to share the story and provide some DIY notes for the community.
My car is a w219, but I also post to this w211 forum given the similarities in the chasses.

1. The Story.

It was a typical Thursday. Get up 6 am and out the door by 6:30 am for work and leave work at 3 pm. Driving home on 15th Street in DC, my car died at a stop light. I tried to tell myself it was nothing, but to keep an eye on it. Later in the evening, I was on the way to the gym with my daughter. While in the parking lot, the car died.

Sweating bullets I was finally able to start the car, and the check engine light was on. My first thought was to bring my car to a "mechanic", but instead, I drove to my garage for inspection. I hooked up my MB iCarsoft II and it showed a code p0335 for a Crankshaft Position Sensor.

2. Notes on the DIY

I managed to do the DIY myself, but I wish I had watched the following videos on this link much more closely:

http://www.mercedesmedic.com/crank-s...sition-sensor/

a) The first thing I did was understand what the sensor looked like so I could replace. Here is a pic,



b) Next, I went to Advance Auto and bought the aftermarket sensor for $38. I would have preferred OEM, but I wanted to get back on the road ASAP.

c) It is very challenging to locate the CPS. It is very small and is buried deep near the firewall, next to the transmission bell housing, on the driver's side. It probably took me at least an hour to find it. You can look at pics on the internet, but it will still be hard to find. Here are some pics that may be helpful,



d) Now once you confirm the location of the CPS, you have to get it out which is no easy task. I find it very funny the articles on the internet that say this DIY takes 20 minutes. Sure it takes 20 minutes if you know the location of the sensor, do not make any mistakes and have the sensor in hand, but how often would the stars align like this with any DIY?

That being said, removing the sensor took me about 4 hours. Yes, 4 hours of blood, sweat, and tears. First of all, the sensor is really hard to get to. I literally was lying on top of the engine several times to try to dig it out.

Speaking of mistakes, it is really critical to use an E8 torx socket. I wasn't sure about the socket size so I experimented with several different sockets. Since I could not see the sensor while my hand was buried two feet in the engine compartment, I could not see whether the socket was fitting. Eventually, it dawned on me after hours to test the E8, and sure enough, it fit perfect.

Even with the perfect E8 socket, finding the combination of a socket wrench, extension, and other tools was maddening. Not to mention find the correct angle to get it out.

Eventually, I removed the sensor and was relieved when my CLS started right up! I cleared the code and it didn't return and have driven about 100 miles and the car feels perfect.

Later I thought about it and recalled that the car was starting a bit more slowly as of late. I had thought that was due to the vehicles age and the cold weather, but come to think of it this was probably a sign the CPS was going.

3. Bottom Line.

Don't let the stealership rob you with this repair. It takes time but is very doable. I'll even keep an extra CPS with tools in my car in case this happens again to again to avoid getting stranded.

 

Nice work saving money and getting your issue taken care of. How many miles did you have on your cps before it went south?

Keeping an extra might not hurt, but keep in mind that if you try to change your cps while the engine is hot, you're gonna have a bad time. Whenever I've had to do this job I simply cannot without letting the car sit and cool overnight.

 

My car has 66k miles.
Yeah, I guess I wouldn't have been very happy if I reached into the engine bay with it sizzling hot!
Have you done this job many times?
Seems like this is a common problem for the w219/w211 chassis?

 

It seems to be a common problem for Mercedes regardless of chassis. I've done it twice on my W210, once on my old W211, and once again on my current W211. As your car ages, be careful of the plastic harness that connects to the CPS. It can become brittle over time and if you accidentally destroy it when disconnecting/reconnecting the sensor, you can get an intermittent connection to the CPS that will mirror a bad/doa CPS failure.