Ford evap leak troubles

[buck91]

Trying to diagnose a P0457 code on the wife's 2014 Explorer 3.5L GTDI (ecoboost). Started as a warning on the instrument panel to check the fuel cap, which on this car is quite the joke since it has Ford's capless fuel filler. After a while the CEL popped and Forscan Lite shows a P0457 evap leak, likely the fuel filler cap. If I clear the CEL it stays off for a while but always comes back. Tried a little shotgun approach and replaced the charcoal canister vent solenoid; note the purge valve seems to work just fine. Tried the manual filler cleaning procedure which is much touted on youtube with no changes (I was very thorough). No odors or visible leaking of fuel. Some light conversation with the dealer and they swear up and down it can't be the fuel filler neck (well not CAN'T but 99.9% it isn't). Without a smoke machine I am kind of stuck, at this point my next step is to pop the right rear wheelwell out and visualize the filler neck and the vapor hose for obvious signs of damage or leaks. Might have to make a DIY smoke machine, though. I do have a Halloween fog machine would that work? I have some PEX tubing which fits the nozzle, but it seems like that fog likes to condense pretty rapidly.

Below are a couple shots from Forscan. Any thoughts?

P0457:

 

[Trav]

Is there a way you can plug in or put a cap over the filler as a test? I suspect the filler just going by the size of the leak.

 

[buck91]

Well, not really. I could disconnect from the vent solenoid. Actually, I did some more digging on my obd2 adaptor and Forscan and I believe I can run the adaptor with my laptop which means I should be able to utilize some of the more advanced features in forscan to check and see a couple things. Its also possible the purge solenoid (which, incidentally, I cannot find ANY part numbers for) would be stuck closed. If I can manually command it to open with the forscan then I could check for vacuum there... Otherwise, I'll have to check for vacuum at the vent solenoid connection. Maybe make a DIY smoker for the tank.

 

[2strokeNorthstar]

Get a cheap cigar and a piece of hose. Fire it up and blow the smoke in. Works really well. Taste terrible but so does spending $150 on a smoke test. Diagnosed my BMW better than the mechanic. I had to show him where I saw the leak and he had to crank up the pressure to replicate / find it. He thought it was fine with the initial test.
My 01 F150 the EVAP test never completes. Even after years and 1000's of miles. Never fails just never completes. Don't know why.

 

[bdcardinal]

Filler necks and purge valves are really common on these.

 

[michaelluscher]

FORScan on a laptop has some bidirectional control, you'll probably be able to control the purge/vent solenoid while smoke testing

Halloween smoke machine is a good bet, that's what I use for vacuum leaks

But if it's under 8y/80k miles, this should still be covered under emissions warranty, think about this if any expensive parts are needed

 

[buck91]

88k.

 

[buck91]

Well for what its worth, after messing with the purge valve duty cycle in Forscan it became apparent that it was stuck. Some moderate tapping with a small hammer and a couple squirts of brake cleaner freed it up. For now. Can't find a replacement part number on a couple different of my go to websites so I'll have to call the dealer...

 

[bdcardinal]

DG1Z-9G271-B

Only serviced with the line the valve is on.

 

[buck91]

Originally Posted By: bdcardinal
DG1Z-9G271-B

Only serviced with the line the valve is on.

Thanks! That thing wasn't listed ANYWHERE. Even the local dealer gave my the vent solenoid p/n.

 

[bdcardinal]

The description is "tube assembly, also includes VMV valve." VMV is Vapor Management Valve, also knows as the purge valve. Fortunately the tube has quick disconnects on each end.