Yup, another small evap leak thread... I'm not sure what else to do. Specs:
'07 Rubicon JKU, just over 90k miles, Auto. Other than a tuner, nothing done to the JK. Tuned for 89 octane, medium throttle response.

Here's what I've tried so far to fix the issue:

- New gas cap- inspected original, nothing wrong with it, but swapped it anyway. Not getting a gas cap light on dash. Just figured I'd mention it, since this is the "go-to" answer most people give at first.
- Relocated the Evap Canister and inspected the canister and all lines, didn't see anything wrong. P0456 was there prior to the evap canister relocation.
- Changed the Integrity Module Detector and associated o-ring when I relocated the evap canister. It didn't fix the P0456 for long, but this did fix the P0455 code.
- I put some epoxy putty (good for fuel tanks and such) to seal around the vapor vent tube nipple at the gas tank, to seal any possible cracks there.
- Replaced the PCV valve.

What else is there to check? I was good for a week (longest stretch of no stupid check engine light due to this), but it came back on today. I've been dealing with this for almost 2 years. I'm getting real tired of that light.

 

The only improvement I'd suggest is to drop the tank and fully seal that nipple. I drilled mine out and smoothed down a vacuum fitting to slide in there. Smothered both ends in epoxy and got it glued up....while taking care not to seal off the has gas tank vent with epoxy. On the occasional day I'll get the code, but it's once in a blue moon anymore.....maybe once every six months.

 

Have you considered a smoke test? Around here, that runs about $90. It might be worth it just to stop chasing it.

 

I've been thinking about doing a smoke test, but haven't looked up how much they are here. Considering where I live, I'll have to assume it's ludicrously expensive- just like everything else around here...

I've been trying to hold off on dropping the fuel tank- though, seeing as how it's been so long and trying everything else that's been done to fix the issue, I think it may be time... *sigh* Frak. I wish Jeep or Chrysler, or whoever owned the company didn't cheap out and use plastic nipples in this application. WTF were they thinking?! Also- I wish this stupid code didn't prevent me from passing SMOG, since it has no bearing on the operation of the vehicle, nor actual emissions. So stupid.

I appreciate the suggestions- I will probably drop the tank before I pay for a smoke test. But I'll do a smoke test if I have to.

 

Heck.. at least ask the price for the smoke test. It's usually a standard fee. Then you can decide from there?

 

I'd put some lube or something around the hopefully new integrity module gasket and see if that helps it. That's the problem with mine. Without a tight seal there it always had the code.

I guess you could also try replacing the purge valve and checking the lines in that area by the battery. It's just an emission problem so you have time unless you are due for inspection. Then I'd pay the $100 for a smoke test.

 

*snaps fingers* Frak! I knew I forgot something- the lines around the purge valve!! I'll check those today. I may order a purge valve to have on hand, just in case... I'll also start asking around to see how much a smoke test is. The Integrity Module gasket is new- but y'all are correct, I didn't put any added lube or sealant around it... What would be the best stuff to use? Thanks again!

 

I would hold off on ordering the purge valve. I can't say where I've seen one bad. As far as lube on the gasket- I've done it both ways, dry and silicone. I like the stuff from Harbor Freight, it comes in a gray little squeeze tube and it's like $3-4. I use it on my sway bar links so they'll slide on after playing in the dirt all day. Works like a charm.

 

So just standard silicone lube for the o-ring then? Sweet. Wasn't sure if there's anything special I'd need to use due to heat or anything.

I inspected those lines going to the purge valve, and they look okay... But who knows? There's some small dings and such, so maybe a small hole I'm not seeing. I've wrapped them up in electrical tape just in case. I might get some heat wrap or something if/when I find myself in a parts store... Again- thanks for help y'all!

If the electrical tape around those lines and the silicone on that o-ring don't work, I'll go get a smoke test done.

 

Yea I've never seen a bad purge valve yet.