5 Attachment(s)
Fuel leans way out when closed loop turns on, then normalizes
This weekend was very cold where I live, around 20 degrees. I took the opportunity to tune areas of the open loop table I haven't been able to hit yet. I noticed when the car transitions from open to closed loop, the fuel leans way out for about 20 seconds then reels itself back to commanded AFR. At first I thought it's because I was commanding a too-rich mixture of ~13:1 at the transition point of 91 degrees coolant temp and that was throwing it off somehow. I went back and leaned it to 13.3:1 and the transition leaned out even more! Is there a table somewhere I can adjust to prevent this crazy lean swing?
Here's the log running my original open loop table where the afr is 13:1 when it goes into closed loop. You can see it leans out to 15.45 before settling down 20 seconds later.
Attachment 140072
And here's the log where I leaned it out to 13.3:1. You can see it leaned out to 16, maybe more. My wideband only goes to 16. You can also see it's running leaner than commanded during the whole log, not sure why. I only changed the open loop table.
Attachment 140073
