So had the car on the dyno. I have an EAM Wideband installed and connected to the ELD so i can datalog it. Now i am using this on an offroad application. Meaning it is not street legal vehicle.
So after a couple of laps on the track, the log is showing it running where the guy from the dyno had it at, but then it starts to get a little richer. I have worked with the guy for a while now to understand most of these things including taking classes to help grow my tuning skills. I go back to him on so much i am surprised he has not asked me to not come back. But when he is not sure why the AFR gets richer after a couple of laps(yes it stays the same AFR after those laps), its hard to dyno the car to get it correct. Yes we can do street tuning way. But he has not seen this before. It was doing this last year also when i watched the logs. we have watched everything and cant seem to figure it out. If we get a caution during the race, when we take the green again it does the same thing. So its not because the motor is cooler or anything like that. i am keeping my temps in the 195 range at all times. all new sensors and injectors are on this motor. did the same thing on last years motor also.
My Dyno guy has helped me out so much this year i am not going back to the old guy. Not when he would not return calls or help last year when i had issues. But we cant seem to figure out why my AFR would show richer after a couple of laps. oh and yes, new AFR and corrected numbers were also put in to make sure everything was correct and in good shape. Still does it.
AFR changes after a little
Re: AFR changes after a little
If the ECU goes into a safety mode it targets a richer mixture. If that is the case you're either running too much timing or have lessened the ECUs ability to apply knock retard properly when needed.
Re: AFR changes after a little
Its only a little bit that it changes. matter of .25 to .75 richer. that is all its changing. No codes or erros show up.
Re: AFR changes after a little
No codes would be necessary for that. A little richer is likely one of the enrichments you have access to.