Chevy Sonic 2015 1.8 hatchback. The air fuel ratio commanded is showing 9.76 to 1. I have replaced O2 sensors, catalytic converters, MOS sensor, and I can't get this car to run more lean. Ideas?
I'm assuming that AFR gauge is aftermarket or part of a ultra gauge type of thing , no check engine lights ? Your going by the reading only ? Black smoke out the rear ? If it was that rich I would suspect an engine light to come on since these cars have sensors all over .
I know it can get frustrating and expensive throwing parts at a car and not fix the problem I had time when I went to jiffy lube and the dude who put the air filter in had it smashed sideways and a check engine light came on since the filter was blocking the air way stupid stuff like this if you have no engine codes I would look at the gauge your using too could be defective with sensors all over reading the AFR at the ECU you should see something the throttle body is elec fly by wire could not be opening right etc .