MSefi.com read only forum (Jan.15,2018)

I have been running my truck for a couple of months now with no problems. Its a 350 running a MPFI setup with an LC1. I got it tuned with tuners studio and drove it (30 miles each way) to work to see what kind of mileage I was getting. On the way back while driving I lost AFR. It was tracking and then it was all over the place and I was having a hard time keeping the truck running after that. I had my laptop with me, so I hooked it up and started checking things out. I found that there was nothing selected for EGO sensor under calibrate AFR. While the motor was off, I selected and wrote to controller LC1 default. That is what it had been set to before. It showed that it wrote to memory. I closed the box and started the truck with the same result as before. Shutting it down and checking, it still did not have an EGO sensor selected. Trying a few more times, power cycling, etc. did not create a situation where it would write and hold the setting. I had experienced this while I was tuning and just wrote a new profile to get past it since I wasnt far into tuning. I would like to fix it so that I dont have to keep doing that every 3 months. Any suggestions as to the cause or possible solution? Thanks.

jbd,

That is not a setting for MegaSquirt, it is a command to TunerStudio to tell it what table (of 10254 elements) that TS should burn to MegaSquirt. The appropriate table is burnt, and retained. TS does not remember what table was burned though, because there is no real need to. And it is the same for MegaSquirt - it remembers the table values, and has no idea about the command used in TS to send the values.

See: http://www.megamanual.com/mt29.htm#oa

All of the flash tables in MegaSquirt (coolant temperature, intake air temperature, wide band response, MAF response) behave this way.

Lance.

Thanks, Lance. That makes sense. I guess I have to do some more digging to do to figure out why I lost my AFR.