Hi, I have a 2006 A3 2.0T with 72k miles. It has an APR Stage 1 chip and runs perfectly - doesn't idle rough, doesn't sputter, really doesn't have any indication of an issue.

However, the check engine light is on. I had a shop look at it, and it was throwing the P0300 and P0303 codes. They did a full service (plugs, filters, oil, etc.) just to refresh everything as they said it looked old (I got the car with 55k miles from a dealer), cleared the codes, and a few days later the light came back on. I took it back and got the same codes, so they replaced coil #3 and gave me some fuel additive to clean the injection system. 50 or so miles later, and the light came back on. This time, it's just P0300.

It's worth noting, at the first visit to this shop, they pointed out that the engine cover was cracked near the intake - see the pictures attached. Could this be the issue? Is there anything else I should be looking at?

Any thoughts appreciated.