Check engine came on then I changed the car battery and light came on again then after a couple days of not driving it. It turned off. Not sure what’s going on.
When the check engine light comes on the car stores a code that tells why. Go to a good independent shop and have the code read. That will tell the mechanic what the problem is.
If the light comes on, you have a problem. When the light goes off and stays off, the problem went away…for now. If it comes back take it to your favorite independent mechanic for a diagnostic check where they will read the error codes stored in the car. Then it can be fixed.