evap emission system leak

[rltu]

My 2001 Expedition obviously has a leak somewhere, as the 0442 code keeps returning. I replaced the gas cap, but it is not an OEM version.

Whats interesting is that when I stop and shut down the engine, I note a rather strong gasoline smell at the left rear wheel well. Looking underneath, I see no visual evidence of a leak. This smell seems to be a big clue as to the location of the leak in the EVAP system which is setting the OBD II code 0442 code. Any thoughts on how I might search this area for a leak?

What concerns me is that I had a JL mechanic replace the tank about 2 years ago, and the connections to the tank may be leaking. But again, no visual evidence is to be seen.

Next time this occurs, perhaps I should pay particular attention to the gas cap to see if it is coming from that point.

Any, all thoughts would be appreciated (wish I had a car lift!)

 

[toms89]

It could be the fill hose or vent lines. It is a sealed system so that fumes are not vented to the atmosphere. If its not completely sealed it can set a cel. I would feel all around the fill hose to make sure it is not compromised. The vent lines are hidden above the fuel tank and cannot be seen with out dropping it.

I would also be concerned with a replacement cap that is not oem.

You likely may not see any fuel leaking if that's what your looking for. Fuel vapor may simply be escaping.

 

[toms89]

Sorry..... double post.