Procedure to test a Crank Sensor.

[sp4bmw]

Can someone detail how best to test a suspected faulty crank sensor please, my car displays all of the hall mark signs of a faulty sensor, cuts out when warm, only restarts when cools down etc etc, also, where is best to get one from other than MB direct, it is a 1992 SL300 24v?

 

[television]

You need an ohmmeter, and it should be 1k ohms when good and in excess of 100k when bad.

Just pop it in some hot water up the the connector end and warm it up to 100c.

Cheapest from Bosch service centers at £47

 

[sp4bmw]

Thanks Malcolm, please can you expalin further? at present I have the sensor wire plug disconnected and the sensor is free from the bell housing, do I simply measure the resistance over the two contacts within the round plug and look for 1k ohms? and higher indicates a fault? I understand that heating it in hot water will make it stick, am I corect?

 

[sp4bmw]

Malcolm, just called a Bosch service centre and they said £85, can you give me contact details for one selling at your price please?

 

[television]

Thanks Malcolm, please can you expalin further? at present I have the sensor wire plug disconnected and the sensor is free from the bell housing, do I simply measure the resistance over the two contacts within the round plug and look for 1k ohms? and higher indicates a fault? I understand that heating it in hot water will make it stick, am I corect?

Yes as near as damn it they measure 1k ohm,,when faulty almost open circuit, there is no in between

Try GSF or Euro, Bosch must have put their prices up

 

[rayhennig]

Only restarts when cooler ...

Mine's a 1991 300CE-24 and may have exactly the setup of yours.

I had exactly these symptoms and it was a Bremi rotor arm that I'd installed 18 months before. Problem went when I put back the old one and I now have a brand new MB rotor arm and all is well.

Bonne chance.

RayH

 

[television]

Mine's a 1991 300CE-24 and may have exactly the setup of yours.

I had exactly these symptoms and it was a Bremi rotor arm that I'd installed 18 months before. Problem went when I put back the old one and I now have a brand new MB rotor arm and all is well.

Bonne chance.

RayH

And we have a couple of thread alive where this could be the fault, interesting the way that they can break down when warm