My girlfriend's 2008 VW Beetle (non-turbo) threw a check engine light. Every once in a while, it starts when cold roughly, misfiring very obviously. Shutting it off and restarting clears it up. Most of the time it starts normally.
Anyway, it did it again this morning, and the check engine light illuminated. She shut it off, restarted it, and drove normally the rest of the day. A stop at the auto parts store revealed Code P2279 Intake Air System Leak.
Any ideas on how to diagnose this? The car is running normally now.