Small Evap leak, P0456

[Rough]

As information for anyone dealing with P0456 (2007 3.7). Completed the following without finding any leaks: Smoked entire system with home made smoke machine. Evap lines between solenoid, cannister, and tank also checked with light air pressure and soapy water. Solenoid, charcoal cannister, and leak detection pump tested for leaks. Filler neck connection and clamp at tank checked, fuel cap removed and filler neck sealed with plastic and duct tape to ensure leaky gas cap wasn't causing code. Only place left is the fuel tank. Dropped the tank, plugged fuel inlet, one evap line, and filler neck. Sprayed soapy water on the two plastic evap ports and the top of the fuel pump then added light air pressure into the tank through the second evap line. After about 45 seconds a small (very small) bubble appeared at the fuel pump retaining ring. Ring is rusty but intact, however, upon removal of the retaining ring I found a small section of the plastic fuel pump housing had deteriorated (crumbled) enough to allow the pressure loss. Leak was so tiny that you'd never see any smoke while the tank is installed in the car. Replaced pump housing, retaining ring, and sealing o ring. Two weeks, several hundred miles, with system self test, no code. Three photos attached.

 

[lfhoward]

Thanks for posting this. As out Jeeps age P0456 will plague more and more of them. I have tried to sort that code on my in-laws’ 04 WJ to no avail.