My check engine light came on last week, so I went to AutoZone, and they pulled up code P0442, which is a small leak in the EVAP system. Has anyone dealt with this before? I tried the common suggestion of checking the gas cap, but it’s a capless system, so I don’t think that’s the issue. Not sure what to try next—any help appreciated!
With a capless system, an EVAP code like that often means there’s an issue with the filler neck’s internal seal. You could try spraying some carb cleaner around the filler door to clean out any dirt on the seal. If that doesn’t work, it might be time to have a shop look at it for a deeper inspection.
The EVAP system includes everything from the gas filler flap to hoses connecting it to the tank, a vacuum sensor, tubing to a charcoal canister, a purge valve, and more. A small leak or a faulty purge valve can throw that code.
If you don’t notice any loose or damaged lines, the next step is a smoke test to pinpoint any leaks. Sometimes, filling up too much can get fuel into the EVAP lines and set off the sensor, which may clear itself after a while.
WAIT A SECOND!
Are you sure it’s code P0442? Because P0042 is actually a code for the oxygen sensor on bank 1 sensor 3.
@Paxton
My dad checked it out but didn’t see any damaged lines. I always go to the same place for oil changes and never had this issue until now. I think I’ll need to take it to a mechanic.
With the capless system, take the funnel near your spare tire and insert it into the filler a few times to help clear any dirt that could keep the flap open slightly.
Kai said:
With the capless system, take the funnel near your spare tire and insert it into the filler a few times to help clear any dirt that could keep the flap open slightly.
I tried that earlier and disconnected the battery to clear the light, but it’s still on.
Could be the purge solenoid going bad. Try removing it and blowing through it; if air goes through, it needs replacing. Tons of YouTube videos show how to do it.
If that’s not it, a smoke test is your best option since the EVAP system stretches across the car. Besides the filler area, the purge solenoid, canister, and EVAP lines are key spots to check.