Hello all, I have a 2018 suburban with the 5.3. The last 3 winters we have had an issue with the catalytic converter getting plugged and causes misfiring. We get codes for the mass airflow sensor (we replaced it) map sensor (replaced) codes 420,430,300, 106. We get the flasing check engine light with traction control dissable and stabiltac disabled message. Last year the mechanic walnut blasted the exaust valve stems. Plugs and wires have been replaced. Has anyone seen anything like this? Truck only has 150k miles.