My check engine light is on and I'm getting code PO 446 Evaporator Emission System Vent Control Circuit. I researched the internet and found one site that instructed to clean the Cannister Vent Valve and maybe even the cannister itself to eliminate this problem. I don't know where this is on the vehicle. I don't want to damage my car by ignoring the problem but I do not know how urgent it is to repair this issue. Please advise if you think I'm on the right track and if so where this item is on my car, and how urgently I should be addressing this issue. Thanks ! Also - after clearing this code the reader showed a 2nd, 3rd, & 4th code. First I received code PO 300 - Random Multiple Misfires, then code PO301 - Cylinder 1 misfire then code PO 303 - Cylinder 3 misfire; however, the engine runs as smooth as ever and I have not felt any misfires or rough idiling. Spark plugs were replaced last at 60,000 miles.