How to replace crank shaft sensor on Mercedes benz c280?

Here are the instructions for the crank position sensor in your C280. Its not hard, just 1 bolt, and a connector.

1.Prepare yourself for a job that is to say the least "not fun".
2.In addition to your normal set of tools, you will need a tiny (mechanic's style ignition set) 5 mm wrench. A socket will not fit!
3.Once you've got a lot of stuff out of your and before you're-assemble everything, take a serious look at replacing the following: 2 rad hoses, 1 thermostat bypass hose, 1 thermostat, 3 belts, camshaft sensor, oil filter (as it is in the way & must be removed)
4.90% of this job will be done from the bottom, so put the front end up on axle stands or ramps (preferred as axle stands can get in the way for this job).
5.Disconnect negative battery terminal.
6.Remove upper rad hose.
7.Loosen the four 13 mm crank pulley bolts.
8.Remove all three belts.
9.Remove oil filter and you might as well drain the oil too.
10.Remove crank pulley.
11.Remove upper (1 center nut) and lower (2 side bolts) harmonic balancer shroud.
12.There should be no need to remove the harmonic balancer or crank bolt.
13.The sensor is located behind the harmonic balancer towards the bottom. Observe how the sensor is installed. It is possible to put it in backwards (don't ask). Remove the two 5mm bolts securing the sensor. You may have to put a socket on the crank bolt and turn it clockwise to allow the sensor to clear the vanes that the sensor cradles. Disconnect the two connectors up top. Be careful as old plastic = brittle plastic.
14.Spray some WD40 or equivalent on the electrical connectors for good measure.
15.Snake the sensor and wiring harness into place.
16.Loosely tighten the two 5mm bolts. Have a buddy slowly turn the crank bolt again to ensure the sensor clears the vanes. Think of how a caliper clears a rotor and must sit squarely upon it (thanks Wayne). OR, If you are made of money, in which case you would never be doing this job in the first place, buy Ford's feeler gauge designed specifically for this purpose. I would still double-check the clearances anyway!
17.Final tighten the two 5 mm bolts and check the sensor's clearance on last time.
18.Re-connect the two connectors up top.
19.Re-attach crank pulley. Rotate the pulley until all four holes line up. It is possible to force the pulley on wrong!
20.Put on three belts.
21.Tighten crank pulley bolts.
22.Attach upper rad hose.
23.Replace oil filter and add oil.
24.Attach negative batter terminal.
25.Start 'er up. The ECM will have to re-learn idle!
26.Be proud knowing you saved yourself several hundred dollars in labor.