Check engine light came on and went off. The code it gave me was p0013

What is your question?

The code says it is exhaust solenoid out of alignment The light went off came back on when filled gas tank went back off and has been off for 3 days Car is running great no problems with it at all. CONFUSED!

What makes this problem better or worse?

N/A

How long has your 2012 Buick Verano had this problem?

ON AND OF FOR 1 MONTH