Well I had the dreaded code as well. After finally straightening out my piece of junk tune from RIPP superchargers (thanks EVANS TUNING) I decided to take this problem head on. I bought the new gas cap, EVAP canister, EVAP pump, O-ring for pump, and Leak purge valve, all OEM parts from dealer. With the military discount wasn't bad under $150. I took off the Poison Spyder EVAP skid plate and started to replace all parts, while checking the lines. I used the silicon, after everything was thoroughly cleaned I decided to wrapped both hoses near battery with electrical tape twice just to make sure. I'm hoping this rectifies my problem, and I can finally get to drive my jeep and enjoy it.

 

Electrical taping every single tube I could find close to the battery under the hood & buying a new gas cap did not solve the problem. Buying these from quadratec solved my problem.

1 51315 0001 MOPAR EVAP INTERGRITY MOD DETECTOR JK 4861962AA 31.00
1 51315 0002 MOPAR VAPOR CANNISTER SEAL JK 52129436AA 5.00

 

Well after replacing all the parts I mentioned, and taping up the lines, I'm happy to say no codes. All fixed and inspection is done.

 

After getting the P0456 Code I bought the Evap Canister and Detector assembly. It totally cleared the CEL light. I took the stock stuff apart just to see what it was like inside. I swear the gasket between the Canister and Detector was the only thing that looked worn/bad. Advise for anyone who gets this P0456 CEL is just try replacing that gasket is a good start. Can't hurt, you'll have to buy it anyway.

 

And it must make a good seal. I suggest using some siliconn or maybe even gasket sealer. I just went through this for months and it turns out the dealer gave me an incorrect part but it came back even after it cleared for a few months. Paid a local shop to smoke test it and pressure test it and it was slightly leaking at the gasket. It was a brand new gasket, evap canister and integrity module. Even brand new it leaked. The gasket from the dealer was a different color so that maybe had something to do with it. It was green.

 

FYI ....replaced Evap Canister and O-ring and no more CEL popping a P:0456 code.
6 minute repair.. and 50 dollars in parts from Quadratec.
replaced evap canister just because it is 9 years old... and the white filter in there was dark gray.
swear it runs better since i replaced it... probably just me.

good luck...

 

I know it's regional, but how much was the smoke test? I'm fighting the code and after replacing the ESIM, gas cap, and gasket, I think I'm due for the canister next if I don't go in for a smoke test.
Was/ is your canister protected by a skid plate? I'm throwing a code and I've replaced the gasket/ o-ring, but I'm wondering if maybe it is just flat out, worn out within my skid box.

 

I can't see the canister going bad unless it was physically damaged. The smoke test ran me $80. I found a nice small local shop.

 

Has anyone tried a DIY smoke or vape test to find leaks?
Where and how do you hook up to the system with a DIY test?
I have a small evap leak and the gas cap message. Thanks in advance.

 

Start with a new oem gas cap. Then integrity module o ring, then replace integrity module, then purge valve, then maybe evap canister if physical damage is shown to the unit.

Check evap plastic lines that are next to the battery. They sometimes rub.

My theory on this after pulling my hair out is that not many people actually have a leak in the lines. It always comes down to those units specifically the o-ring not making a tight seal. You could play parts roulette with it for the same price as a smoke test or buying the kit from harbor freight to do your own.