[Jethrow]

Very interesting Treeve, thanks for the share.

So I understand the closed loop bit, which you explain where the ECU and sensors work together to target the 14.7 AFR. But to go further, does the ECU then deliberately move the target plus and minus around the 14.7 to achieve the cycling? Would I see that on a trace if I was logging AFR whilst say holding the revs steady?

Also, if I may, for my test where I registered low hexane (3ppm) but high NOx (140ppm) do you think if I enrichened up the car it could bring the NOx down to an acceptable level with only minor change to the hexane? As indicated by your graph?

Tho to do that, I might have to give the ECU a new closed loop richer target if that is at all possible.

Thanks again.