Check engine light
 

So, my check engine light will come on spontaneously and be on for about 2 or 3 days no matter how many times I turn my car on and off. Then it seems to disappear for a week and I'll forget about it, and then one day when I start up, it will be on again.. and the cycle continues.

The mechanic has done a full inspection and hasn't noticed anything wrong with my car other than it soon needing two new front tires. So I can't imagine what the check engine light could be on for.

It's been suggested that maybe it is just a sensor problem, but there must be SOMETHING happening at start-up to decide whether it wants to be on or off that day. It's really becoming a pain in the butt, and I'd rather not bring it in to VW for a scan unless I really have to. The dealership is rather far away.

Any ideas?

RE: Check engine light
 

Mine did that, and I replaced an O2 sensor and never came back, my car is weird...if I don't close my gas cap ALL THE WAY! the check engine light will come on until it clicks....funny huh? I never got it scanned or anything like that, I just knew it needed to be changed with the amount of miles that were on it at the time, it would've been time to change it anyways, it just so happened that it fixed it.