last month i was doing tech at my local autocross, and I come across a miata I'd never seen before, and as i look under the hood I see it's turboed. I'm always glad to have another car in the miata mafia, so I hunt down the owner.

He's a kid, this is his first car. It was a trade in at a used car lot his dad works at. He knows NOTHING about cars, turbos, megasquirt, etc (he doesn't have a computer he can even hook it up to). I start talking to him, and he said it doesn't run very well, and the wideband consistently reads 7.5-8.2, and backfires a lot. Since I have tunerstudio and done megasquirt before, I offer to help, and a few days later he shows up at my house.

I get hooked up, and think it's running rich, so I'm explaining how MS works to him, and we drive around and I put it on autotune. As expected, it starts pulling massive amounts of fuel. But the more fuel it pulls the more the engine bucks, stalls and stutters. Eventually we limp it home, and I put back the original settings, so it will at least run.

that's about all i had time to do. I did notice that the injectors are read tops, which i dont think is stock for the 1.6 in a 90. So maybe the previous owner upgraded injectors but didn't change required fuel? I don't know.

Since it got worse with autotune I'm nervous the wideband isn't reading correctly, so I'm going to change that. I don't know anything about miata stock settings, are these eve nclose?

 

Find the numbers of the injectors. I'm wondering if they are 460's.
Make sure the AFR target table looks good, make sure the wideband is calibrated right.
Then autotune it.

 

Dead wideband?

 

^second

Try calibrating the WB, if it can be calibrated.

 

Well the injectors are the 460 rx7 and it dropped the required fuel from 7 to 5.8. I'm going to calibrate the sensor on friday

 

why bother on this moron?

 

Have you ever worked with young adults? Most are morons at first. Some snap out, some dont.The ones who snap out, are the ones who make it all worth it.