Couldn't tell you, but it does need to be in the evap emissions system. It looks like a simple baffle that regulates the fumes coming in, but I do not know the flow of the system.

 

2013 Moab edition. 130k miles. Getting P0456 intermittently. Mainly when tank is about empty and I refill it. Light comes on within 50 miles. Re-set it and it stays off for a while.

what I’ve done so far:
1. New gascap
2. NEW purge Valve
3. New valve and o ring on charcoal cannister.

in checking the lines I didn’t see anything obvious other than it appears one of my hose clamps on part of the filler neck is half missing. Could that being loose cause a P0456 code?

 

Possibly- is there enough of the clamp missing, such that it is no longer doing it's job? If so, then there's potential for a leak. Don't forget to check the other lines around the engine bay- there should be a evap diagram under the hood showing all the lines and such. I stupidly missed a couple lines around the engine bay.

 

yeah it looked like whole backside of clamp missing. But it’s a weird design. I tried to pull off the rest of the clamp but it wouldn’t come lose. It’s like it’s molded into the rubber. I didn’t want to tear it so I put the new clamp right next to it and tightened it down pretty good. We’ll see on next fill up if that did the trick.

 

Yeah, those hard lines are a bear... If your fix didn't work, just get a replacement line, they're not that badly priced.

 

Here is old next to new. You can see some kind of plate on the old one and when I tried to lift up on it, it wouldn’t budge and seemed to be taking rubber with it.

 

Well the code came back this morning when I used the remote start. So the clamp probably wasn’t the issue. I have noticed the majority of the time the code throws when I use the remote start and it immediately shuts off because of the check engine light. Cleared the code and drove 30 miles to work and didn’t come back. I guess it’s on the mechanic for a smoke test whenever I have the time
to leave it. It’s just a hassle.

 

Check this video out, might cover your issue:

 

Thanks, yes I saw that video when researching this issue. All the nipples look intact. And no flex.

so far light hasn’t come back and I’ve filled up and driven about 100 miles since.

im really thinking it has to do with the remote start and that is when it is always thrown the code. But when I can get time, I’m going to get it in the get it tested.

 

Been a few months but I can't figure this out and need help. 09 JK sahara. 98k miles. I'm having the p0455, p0456, and p0457 as well as the GASCAP light on the odometer. Mostly the p0455 code. It's nearly every time I drive and I cut it off with a cheap code checker.
parts I've replaced
-entire gas tank assembly (replaced right before I bought it)
-vapor canister (aftermarket)
-integrity module/ leak dec. pump and gasket (aftermarket)
-gas cap (mopar)
- filler tube(mopar to one with the valve)
- purge valve (mopar)
- hose from intake to air box(happened to find a crack while looking)
I've spent hours checking hoses, and inspecting everything I can see and feel. There are no rough spots, no cracks, nothing.
I've tapped up the tubes by the battery even though mine weren't touching the battery.
there is a slight fuel smell from the passenger rear every once in a while like I've read a lot of people have said.
The nipples on my gas tank are brand new, all the
tubes look new. I've tried every fix from the dozens of threads I've read and tried all the common fixes that I've seen other people do to fix it. This is driving me nuts and I want to get rid of the stupid thing. I should have listened to my gut and stayed with a Tj. I never had issues with any of my Tj's or my Yj.
looking to schedule a smoke test but not holding out hope.
If that doesn't yield any results I guess I'll drop the gas tank and inspect the hoses/ tubes.
any help is greatly appreciated.