RPM sensor question??

[bmwjc3]

I was wondering if there is supposed to be something on the RPM sensor or is gonna be flat on the end?

Also is there something to look for on the flywheel that signals the sensor?

Last, Does the rpm sensor control fuel signal as well as spark signal?

Thanks Joe

 

[epj3]

An E's flywheel has little 'pegs' that pass by the crank position sensor. It's a simple magnetic sensor (yes, supposed to be flat on the end), but wont work if too dirty or far away from the little pegs.

 

[bmwjc3]

There doesn't seem to be anything on the flywheel but there is a piece of metal on the harmonic balancer looking piece on the backside of the flywheel. I pulled the sensors out to check the ohms to make sure the sensors are good. The local dealership has no listing for an RPM sensor, so I need to find out the proper name of the sensor or give them the part number. Joe

 

[epj3]

I think the part number is 12 52 1 279 695 (via realoem.com) but the drawings aren't right (but they aren't all the time on that site...)

Take that number to the dealer and see what they say.

 

[bmwjc3]

I went to the local dealership and the parts dept said they don't have any rpm sensor listed. They had something called a pulse generator sensor. It looks identical to the 2 sensors I pulled outta the bellhousing.

 

[epj3]

Thats what its called......

 

[bmwjc3]

OK, I will change those and hopefully not have any more probs. I just hope that is it, because I think the ECM would be next. This really sucks being without my ride.