Constantly replacing crank sensors Motronic Basic

[malmeida1040]

I recently purchased a 325e from Craigslist back in December. It ran terrible and turned out to be the ecu. Another ecu was swapped in. Couple months later crank sensor blew out and was replaced. 3 weeks after another crank sensor blew out. Is this a common issue with motronic 1.0? Can’t seem to find any info.


Sent from my iPhone using Tapatalk

[e30sh]

The connectors on the early e's tend to biodegrade. Once you have them both replaced, you should be good for a decade +.

DME's are bulletproof for the most part unless you car leaks.

[jeffnhiscars]

The 2 reference sensors are identical so can easily be reversed. AMHIK :)

[TobyB]

Aftermarket sensors seem to be far less reliable than what you can find in the junkyard.

t

[malmeida1040]

I’m gonna try swapping in new pigtail connectors. Also they’re Bosch crank sensors.


Sent from my iPhone using Tapatalk

[ForcedFirebird]

The sensors are robust, more than likely the wiring or connectors causing the issue.

Aftermarket sensors seem to be far less reliable than what you can find in the junkyard.

t

Can' tell you the last time an e30 came across any yards down here. Stopped by a yard today and the oldest BMW was an e36, also rare to see, and was obviously just dropped since they are a bare shell in a couple days.

[malmeida1040]

Update

Changing the connectors fixed it. Has been running solid and starting every-time.

[e30davie]

This forum seems to be obsessed with suggesting to change the CPS sensors. I reckon a lot of the time it is wiring or connector issues that get fixed when the sensor is changed, rather than the sensor itself. After all the sensor is a very simple device.

[325e '87]

This forum seems to be obsessed with suggesting to change the CPS sensors. I reckon a lot of the time it is wiring or connector issues that get fixed when the sensor is changed, rather than the sensor itself. After all the sensor is a very simple device.

Yeah, it seems that way but obviously it has to be known working to diagnose virtually anything related to engine problems.