M130 Engine Speed and Synch Diagnostic errors, changes CRIP

[jeffkraftwks]

This is a new build on an air cooled porsche with ITB's and Alpha N / TPS based firmware from a vendor. Once the engine warms up a bit we are getting engine speed and synch errors, it appears to be losing its position. The engine stutters/stumbles when the change occurs and it can be seen in the logs.

We have checked wiring & harness. Checked and re-checked air gaps which are within spec per the sensor data sheets. Replaced the crank sensor with new Motec M DHALL HS230 sensor just to be sure. Cam/synch sensor is hall type mounted at end of bank 1 camshaft with a single pin trigger point. Ref/synch appears ok, cycle lock at start up etc.

In the attached log file - if you watch “Engine Speed Reference Diagnostic” you see random errors were it says “Position changed” briefly. You see it happen frequently after the engine was shut off and restarted somewhere around the 3:20 mark going forward. At these points is where the engine stutters or stumbles.

You can also notice that the “Engine Synchronization Pin Diagnostic” goes in/out of a “Small Pulse” status/error but when it does, it does not coincide with the times it is showing “Position Changed” on the speed diagnostic. This "Small Pulse" error happens randomly from early on in the log and also at some point continues after it was restarted.

What exactly does the "Small Pulse" status mean on the diagnostic? Any suggestions for troubleshooting or cause?

Thank you,
Jeff

[jeffkraftwks]

Just a follow up on this issue - suggestions received from the firmware developer resolved errors.

The changing CRIP issue was being caused by the cam trigger being too close to the missing teeth on the crank signal. We rotated the mount for the cam sensor by 120 degrees to separate the signals and that seems to have solved the "position changed" errors and engine stuttering.

The "small pulse" error on the synch was resolved by changing the eng synch pin hysteresis values to match the signal threshold better.

Thank you