My 2021 Mazda CX-9(5k miles) seems to be running a bit rich. CO seems to be excessive coming out of the tailpipe(I have not had it measured but I have followed my own car with the vent open and I was getting headaches after a minute or two of following my own car). I have taken the car back to the dealer and explained the situation...but they stated that the fuel trims are good. So I got a scantool to take a look at the parameters myself. The fuel trims do look decent, but slightly rich and all other sensors seem to be working properly. But I did notice that the Barometric Pressure was reading 15.15psi. I live at sea level and the Baro that day was 14.7...verified on my phone and on the NOAA website for our area. Will this cause my car to run rich?

 

Welcome to the forum

Your Mazda is still under warranty, have Mazda look at it. They will likely also re-flash your ECU and possibly you may get an updated version of it if available.

 

Will do. Thank you,