If anyone wants to try and replace their crank position sensor on the 5.0 V8 (ML 500) you'll find it on the lower back side (drivers side) of the engine. It will be down where the engine meets the transmission. They say (Mercedes Master Tech. from justanswer.com) that you can get it from the top. It will be extremely hard to get it from the top unless you take the drivers side wheel well out and remove a small heat shield. Once you remove those you'll be able to see the CPS. Look for it on the top of the bell housing and behind the exhaust. If you get a long enough extension (like 30+ inches) you can get it from the top. Place the extension along the brake fluid reservoir going in at an angle towards the bottom of the motor. The one bolt that holds it on is a torx (star shaped bolt head)bolt. I used a E8 (tech said T25 or T30, depends on vin) star socket that I got from Auto Zone. Its easy to change out assuming you can get to it. Anyways, good luck to anyone willing to try. This should make it a little easier. I would have taken pictures but its in such a horrible place it was hard to get a good pic.

 

Thanks! That torx size is very helpful. I will be doing mine shortly. I found instructions on mercedesshop dot com in their DIY section.

 

I found that the exterior torx bit must be a 1/4" drive to fit in the tight confines. From there, get all of your extensions and I found a universal joint in there really helps. Once you find the sensor and assemble the 3 feet of extensions, it is an easy in and out. I would recommend work gloves or duct tape on the back of your hand. There is a heat shield down there that is like a knife blade!