SLK55 - Failed Crankshaft Position Sensor

[595Heaven]

Bugger. Took the car out this morning and all was good. Got home and left at the bottom of the drive to use this afternoon, but when I tried to start it, ij just cranks and will not start.

My cheapo OBD reader reported a P0335 code - Crankshaft Position Sensor “A” Circuit Malfunction which seems to be a fairly common problem on these engines. Sensors are about £40 so not too bad.

I know where the sensor is located, but access is sooo tight. I think I need to remove the engine cover and air inlet pipes to gain access, so will leave until I've got a new sensor in my hands.

Has anyone had to replace one of these? Any tips?

[anonymous-user]

I would advise caution with this, if it doesn't come out intact then the gearbox has to be removed to clear the debris... I've been trying to loosen the cps on my W220, to no avail so far. Spent the last week or so squirting plus gas over it, but it's not having it...

[595Heaven]

swiveleyedgit said:

I would advise caution with this, if it doesn't come out intact then the gearbox has to be removed to clear the debris... I've been trying to loosen the cps on my W220, to no avail so far. Spent the last week or so squirting plus gas over it, but it's not having it...

Hmmm.... that doesn’t sound good. I’ve read several threads across the web of people changing these on the V8 and none have mentioned it being difficult to remove / breaking?

[anonymous-user]

Well you never know, it could come straight out or be stuck solid, there's no way of knowing until you try.. I've read of people drilling them out.

[595Heaven]

I’m going to give it a go. Got the new Bosch sensor as well as some 1/4” extensions, a 1/4” UJ and a new magnetic picker upper with built LED.

Will have to delay until next weekend due to the crap weather this weekend though...

[AC43]

I've them done before on various V8 Mercs by the AA on the drive. IIRC both my C43's and my 211 E500. I'm pretty sure one of the C43's had two fail.

The job always seemed pretty straightforward.

Same on the wife's Clio - I think I've had that done 3 times.

Oddly enough, the one on my current 212 hasn't failed (yet).

In the past I've just seen them as service items the AA can sort as and when.