gas cap swap - ZJ to JK?

Getting a small evap leak code (P0456). From reading some forums, the gas caps seem to fail frequently and are the first culprit to check. Alot of people say they go through a gas cap every year or so…sounds pretty shitty, but I’ll entertain the easy fix before having to look at the evap canister! many people have a second modern jeep and mention swapping the gas caps for a week to see what the problem follows. Any idea if the ZJ and JK gas caps are interchangeable? And does the ZJ report evap leaks like the JK?

Now I know what your thinking, why not just try it out?! Well, cause then I wouldn’t be sitting at work killing time and getting paid for it! Figured I’d ask first and get feedback, then DO it afterwards lol

If it’s not the gas cap, then I suspect I may have knocked the evap canister a few weeks ago at G2, although it was probably close to 10 days after that the code came up, and seemed closer to gassing up than to the last wheeling trip. I was able to clear the code for about a week by resetting it and carefully tightening the gas cap, and it just came back yesterday (filled up on thursday night and only drove it once over the weekend, did not carefully put the gas cap on and ensure seal during the latest fill-up).

On a side note, any idea how long a small evap leak code will take to generate after being cleared?

ZJ’s will generate evap leak codes. I’ve got one on mine a few days after the evap cannister got ripped completely off. I replaced the cannister but last year the evap line under the vehicle got ripped off and, interestingly, still no code.

I’d be surprised if the ZJ cap works but its worth a shot. The cap on my car leaks and occassionally triggers the CEL light. The light then clears itself after a week or so. Replacement cap from the stealership was like $80 so I learn to live with the occassional CEL. Been like that for 4 years now.

Thanks for the info Eric, I’ll give it a shot at least.

Honestly I wouldn’t care about the evap leak (until it got worse at least) and CEL, except when the CEL is on my remote starter doesn’t work. I really love having a remote starter! lol

At this rate, seems like I can at least clear it once a week to make my remote start work 95% of the time! But I’ll still mess around with it and inspect the evap lines and canister some day when its nice out.

Few more weeks and you wont need remote starter.

What, you guys don’t start your jeep with the AC on full blast when it’s hot and muggy in the summer? :laughing:

Just kidding, I’m looking forward to the hard top → soft top → no top conversion :smiley:

What is this AC thing you speak of?

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