Evaporative system I had a mechanic scann my 2001 525i and the scanner said the the evaporative system has a problem. The mechanic reset the service engine light. It went off for a couple of days and is now back on again. The mechanic told me that the service engine light may have came on because I did not put on my gas cap on correctly. Im wondering what other reasons the evaporative system would cause the light to come on. Thank you !

The purge cansiter valve may be malfunctioning and the pressure pump that pumps up the tank after being filled may be leaking or going out. And cap may be leaking try replaceing the gas cap seal. you know try KISS Keep it simple stupid, Not calling you that just had to remember that when working on cars as a lot of times you get into really complex problem solveing for something as simple as a gas cap gasket cracking. The purge cansiter valve may be malfunctioning and the pressure pump that pumps up the tank after being filled may be leaking or going out. And cap may be leaking try replaceing the gas cap seal. you know try KISS Keep it simple stupid, Not calling you that just had to remember that when working on cars as a lot of times you get into really complex problem solveing for something as simple as a gas cap gasket cracking.