Wide MAF Voltage/AFR Spread

Hey there!

I have a Mazda RX-8 6-port that runs well but I've had some AFR stability issues for a while. To make a long story short, I decided to check my MAF calibration, so I re-flashed my ECU so that closed-loop never kicks in, set all my compensation tables to be flat, and logged some data.

What I found was weirder than I was expecting. The image I attached shows a scatter plot of AFR readings against MAF voltage. It looks like I'm getting a variation of about .1 lambda at every voltage reading!

I'm guessing at this point, it's a mechanical issue that needs to be sorted out? Injectors maybe? Any input would be greatly appreciated.

I also attached the log file that graph was generated from.

Thanks!

Bryan

Hello this could be caused by a few things but i would start as you have also pointed out the injectors may need a service, fuel filters, pump flow and prssure also check the maf calibration file.

Regards Ross

Thanks!