420 code

What is your question?

But check engine light came on. Had the mechanic want to scan , said it was my catalytic converter. They put a new one in aftermarket one. Drove it for 3 months.Check engine light comes back on. Run a scan showing 420 code. Mechanics said after market kalavergers , burnout , louis fast and he wants me to put a chevrolet gold standard candidate converter into the car. Did not put it in yet , but we'll be scheduling to have it done. However , this morning I start the car up to check engine light is not on. Drove to work.Turn the car off, turned it back on.No check engine light. So is it really my catalytic converter?

What makes this problem better or worse?

Car runs fine. Only thing I see is a check engine light on.And when they scan it , I got the 420 code. But now the check and light is off.

How long has your 2017 Chevrolet Trax had this problem?

More than a week