Last week ive tuned a car for a client and his battery terminal came loose during driving.
he changed the battery to one that fits better but he says that after that his afr's went really rich.

i have the car here now and i have to lean everything out a lot so much that i worry driving it under boost.

ive made data logs to look for maybe damaged sensor data and cant really find annything just the only thing that ive noticed is that with the old battery its displaying around 13.5v while running and now with the new battery its 13.8v

can 0.3 volts make such a big difference on the injectors? And if yes can i compensate it with the voltage compensation in the fuel menu?

normally its set to 0.2volts and can go bellow 0.1v so does that mean i have to set it to 0.5volts?

 

That shouldn’t make a huge difference. What ecu? The ms2 and ms3 have different settings. Sounds like you have a ms2, but my guess is you have something else going on,

 

Its a ms2pnp based around microsquirt module.but i think its screwed.
ive talked to the manufacturer and he said because the battery got disconnected the overvoltage probably fried something in the ecu. Im checking sensor data al day but cant see annything strange.i can post a before and after log.but probably gonna have to send the ecu back to mslabs or order a new microsquirt module.

ps.setting it to 0.5ms/v or 0.6 does lean it out but not enough and its verry unstablle

 

2 logs i made yesterday