97 Jetta GLX - P0440 fault Code

I'd expect you to fail the next emissions test if you don't fix it. In some places driving with the check engine light on will get you a ticket.

Most likely cause is the gas filler-cap is not screwed on properly and is therefore leaking. Screw it up properly and the fault light may go away after a few days.

The other causes are leaks and u/s valves associated with the vapour trap cannister. Diagnosis of this type of problem is moderately complicated. If you don't know how the emission control system works you might want to take it to a dealer.

Charles

Yes, it's a concern since your MIL is on!

The check engine light is not on. I just get this code when I scan the car.

Aside from a gas cap, any other suggestions?

How will this affect emmissions testing if it is supposedly just gas vapor?

Thanks.

- Hugh