Gascap and now CEL code

[BlackKnight]

Does anyone ever get this? I got a gas cap warning last night, and this morning it popped a CEL. I checked online and it says it could be the Evap hoses. I'm thinking that it may have popped a hose because of the very high heat (tank pressure from expansion) and that it may have ruptured a hose.

Does anyone have experience with it? how easy is it to fix?

[BlackNBlue-ISH]

Try swapping the gas cap. The seals on it might've been bad, and no matter how "tight" you get it, it may still leak. I'd start there. What was the code?

[KenCal]

Had a similar experience three years ago. Turned out I had a crack in the evap canister. I replaced the gas cap and the integrity valve[ it's mounted on the evap canister] before finding the crack using a smoke machine. Have your mechanic hook up a smoke machine before you spend money on parts you don't need. RockHard sells a evap relocation bracket, I highly recommend it.

[BlackKnight]

I replaced my gas cap with an after-market Locking one. I'll try to OEM one (if I can find it, LOL) and see if that fixes it. I'll crawl under her in the afternoon, to see about the hoses (which I think is at least a plausible probability).
The first mods I did to her were Skidplaces and Evap Armor plating so I'd be surprised if it had a cracked evap after this much time being armored. But you never know, in either case, I'll have the mechanic do one if I can't find the issue with the cap/hoses...

I'll pull the CEL at lunch, my guess is it will be the generic eval error.

Thanks Guys...

[KenCal]

I had full skids too including the RH skid but the evap lines were still exposed. Something hit those lines and caused the nipple the hose was attached to to crack. Never would have found it without doing the smoke test.

[BlackKnight]

CEL codes are:
PCM P0441; evaporative emissions
PCM P0456; evaporative emissions

[BlackKnight]

Also just cleared the codes, and changed out the cap, gascap code came right back.

Crawling upder to see if the hose has visible issues.

Update: no visible issues on the hoses/no dry rot etc. Did notice one of the electrical connections was a little flimsy but looked connected.

[BlackNBlue-ISH]

Since i'm a google/youtube mechanic....

google leads me to check the vacuum lines in the engine bay, coming off the intake manifold and/or next to the battery. The google search term was the code plus JK to narrow the search to the same general model.

P0441
P0456

and just for fun...

[beaker]

If a gas cap doesn't fix it, you're either left to hopefully find a big glaring problem... or get it on a smoke machine that most people don't have....

[Car Jack]

I'm a youtube mechanic as well. Eric O on South Main Auto just had this issue on a dodge. Turned out that there was a small rusted through hole on the filler neck, just under the gas cap.

[BlackKnight]

OK, so went through everything I could myself and then reviewed.
Other than a wire that seemed "Loose" there is nothing visibly wrong with any tobes/cables, etc, I sprayed the hoses and Evap with very soppy water on a hunch, hoping that maybe a bubble would form, Nope. so I went back to the beginning. Looking at the tank opening and cap(s). The OEM cap gasket hadn't been used in 5 years and was dry. the Aftermarket cap was a bit dusty and there was some sand-like substance inside. that sand-like grit was also around the tank opening. I cleaned everything up and hit the gaskets with WD-40 to try to lube and "moisten" the gasket.

Hopped back in and where I had already cleared the CEL codes that popped up, the "gas cap" code was still there. I drove out to fill the tank for the Class 6 I'd be at on Sunday, and five minutes later the gas cap code cleared. I went all Sunday, and several errands since, and everything is good.

Looks like it was the gas cap after all, just needed to be examined and cleaned properly. and lubed so it could make a good seal...

I guess that sometimes it's best to go back to the beginning and thoroughly check everything...

[KenCal]

Glad to hear Bob, Sometimes it's the simple things.