On my way home last night my CEL came on out of no where, I just pulled the code now and got a 01-11; problem with EVAP system. The sticky says that this code can point to so many problems that is pretty much useless, so this weekend I wil just have to look over everything,but my question is; what does the EVAP system do? How bad is it to drive for a few days when it has some kind of problem?

 

From what I've seen the 0111 code typically indicates a bad charcoal cansiter and valve.

Sky-high overview:

The EVAP system basically helps contain fuel vapors. Once the car is running, the valve opens up and releases the vapors back into the engine for combustion.

 

hmm. Well, I cleared the code yesterday when I check it, and it has not come back since. If there truely was a problem, should the code have come back within an hour or so?

 

Just keep driving If the code comes back (which I'm guessing it will eventually), worry about it then. Sometimes those failures are intermittent - so the code may not reappear right away...