I was just cruisin down the highway when my CEL just went away...i've driven 65 miles since and it hasnt come back, i've pushed the car since and nothing yet so far *knock on wood* not sure what happend but yeah...NO CEL. wtffffffffff
well the only thing i've done to my car today before i hit the high way was wash it, clean the intake filter and started polishing my intake mani :| then i drove it about 1 mile, got on the high way and it disapeared. PS OBD reader isn't picking anything up either
Some CELs will reset after a certain number of miles with no fault. I think it's 50 miles, but not sure. Other times depending on the fault, if you start the engine a certain number of times without a returning fault the CEL will shut off. But as everyone has said, on the Passat the illuminated CEL is a feature!
Don't know if this has been thrown out there yet (I didn't see it), but if you didn't get your gas cap screwed down with several clicks, it will trip the CEL. Usually, it will take until your next fill up and 1/4 to 1/2 tank of gas to get the dang thing to turn off.
That's the first "problem solver" that a shop will tell you. You can always fix it by opening you gas cap, pushing the metal stop piece open and venting some gases, then putting it back on til it clicks. It's rarely the problem, however. You have something else, like a solenoid that will set off your CEL randomly and then shut it off once ignored and not cleared for awhile...it's only stored, not fixed.