2010 Liberty code P0456

[rmp608]

I have this code that will stay cleared for a few weeks then pop up again. Had a smoke test done..no leaks found. Changed purge valve...all new connecting hoses to it in engine compartment...new vapor canister with new leak detection valve..new air vent also. Have till next November to pass state emmisions so I have some time but was hoping someone has had a similar problem and could offer some advise. Thanks in advance !!!

 

[lfhoward]

You didn’t mention replacing the gas cap with a new Mopar cap. Could it be that easy?

 

[rmp608]

You didn’t mention replacing the gas cap with a new Mopar cap. Could it be that easy?

Yes..forgot to mention...first thing was replace with genuine jeep gas cap.

 

[LibertyTC]

Small EVAP leak can be difficult to find. Strange that the smoke machine test did not locate smoke anywhere.
As long as you clear the code before inspection, you should be fine.
Even tho it's a new cap, I wonder if any shop may have a pressurized gas cap tester.
Basically it tests the cap while under pressure.
Sometimes the seal may not be sufficient, and may be worth trying another cap brand & see if that helps.
My locking mopar cap seems to seal very well, as I can push down on it as it clicks into place.

 

[rmp608]

I can only clear the dashboard light . There is a permanent code remaining in the module that has to be cleared before it will pass inspection.

 

[LibertyTC]

That can probably be cleared cleared by removing both battery terminals, tape/clamp them together for 40 minutes. (full re-set)
Ensure terminals are safely away from battery posts while doing so.

 

[rmp608]

Thanks!!!! ...Interesting!!! Never heard that procedure done before...Will try it and report back..

 

[rmp608]

Update..I did that procedure for a hour...still have permanent code P0456 ..

 

[rmp608]

Just to add more info..a few months ago I did the drive cycle procedure to clear the permanant code and it did clear it for a week..then came back on..

 

[larryblevins]

My 2012 liberty went to the dealer 11 times at 30,000 for that code. They did lots of smoke tests even replaced a lot of parts. They thought it was fixed with no codes and once I drove it the code would return. What they finally found was a rubber hose coming off the gas / fill tube area had a hole rubbed in it because it was hard up against the metal in a spot. Setting still no leaks but driving it bounced around and leaked.

 

[Morgplee]

I had this exact same issue on my 07. Turns out it was the fuel vapor leak detection pump. Hope this helps.

 

[rmp608]

My 2012 liberty went to the dealer 11 times at 30,000 for that code. They did lots of smoke tests even replaced a lot of parts. They thought it was fixed with no codes and once I drove it the code would return. What they finally found was a rubber hose coming off the gas / fill tube area had a hole rubbed in it because it was hard up against the metal in a spot. Setting still no leaks but driving it bounced around and leaked.

Thank you!!! I will check out that hose!!

 

[rmp608]

I had this exact same issue on my 07. Turns out it was the fuel vapor leak detection pump. Hope this helps.

I changed the entire charcoal canister..it came with brand new leak detection attached

 

[rmp608]

Update...The valve on top of the gas tank had slight crack . Its seems to be very common on the Jeeps. I was able to epoxy it back into place without having to drop the gas tank. Light is now off!!

 

[JeepLibertyKK]

Your problem has been solved but for others, I had the same issue that drove me crazy trying to resolve on my 2012 Liberty. In my case, it was a plastic EVAP line under the hood, along the firewall. There was a small crack at a 45 degree bend. Never would have seen it, required a smoke test to diagnose.