fuel cut at Load of 48 - 50 RB25

[bachig24u]

Hi Matt,
Can knock trigger events cause a fuel cut at specific load (around TP load index of 50) for instance, if knock threshold is not met?

I ask this because I'm experiencing fuel cut with hcr32_RB25DET.
using 11U10 ecu running TPS firmware for 11U00 ecu and with either a 11U00 or 11U10 binary files.

performed the usually increase 'load cut' (tp limit) to a value larger than the full load TP but same result.
injector max Tpulse is set above 30ms also and practically never reaches 20ms.


Any ideas greatly appreciated.

Simon

[Matt]

Yes this can happen. We saw this issue on a Z32 RB25 setup with the knock sensor causing injection cutting issues (see image attached)

The RB25 knock sensor is incompatible with the Z32 ECU so that was removed and replaced with a resistor and knock problems were resolved.

There is a recent article which Eric linked to on here about the knock thesholds being TP based tables and how adjusting K affects these. It will be necessary to start running through all the ECUs finding these tables since the wrong thresholds start getting used

Make sure TTPmax is initially 255s during tuning and you can pull this back later