Runs well with cam sync, but starts occasionally

[murjam]

Hi!

I'm trying to get the cam sync configured, the engine runs just fine with cam sync, but would only start every other time with cam sync enabled. I was wondering if it could be that VEMS does not actually see the cam signal and just randomly tries to sync?

Starts every time when wasted spark is enabled and cam sync disabled.

http://200sx.idnet.ee/wasted_spark.vemscfg
http://200sx.idnet.ee/cam_sync.vemscfg

The engine is a turbocharged BMW M52 with hall primary and hall secondary trigger.

Thanks for hints!

[gunni]

Are you using the stock M52 cam sensor?

[murjam]

No, I installed one from BMW M50, which should be a hall sensor by diagram fed by 12V (i did the same).

What i have found now searching for analogous problems is that VEMS seems to have a feature to start even without the cam sync. If this is true, then probably the problem is that I just have no cam sync signal. I have added the solder blob to the bottom side and checked that SJ7 is not connected.

When I start trigger log, I actually see no secondary trigger events there, only LESS_STRIG or something like that.

[wersch]

Early M50 have VR on the sync sensor

[murjam]

This is what I just realised, the sensor is from a non-vanos M50, which turns out to be VR, and this is probably the problem. Somewhere it was claimed that all M50 have hall cam sensor.

If someone knows the pinout of M50 cam sensor, let me know.

Thanks for the responses!

[gunni]

https://1drv.ms/b/s!Agm0wZb6As7NpJE5z3-buv4oD8sw6w

Link to it