102417 Other NHTSA ID 10120566 TSB ID NTB17-082 Nissan; dtc p0456 caused by evap leak at vent control valve o-ring if you confirm the mil is on in an applied vehicle with dtc p0456 (evap very sml leak) and - dtc p0456 is not caused by a loose fuel fill cap (refer to ntb13-097). 101417 Other NHTSA ID 10119172 TSB ID NTB12-051k Mil on with dtc p0101 this bulletin has been amended. Oct 07, 2016 2 EVAP Codes; P0442 and P0456 Postby cbova Mon Oct 23, 2017 359 pm The wife&39;s 2012 Pathfinder with 98k miles on it just started with these 2 codes first was the P0456 (very small leak detected) then eventually the P0442 came too. I first removed the canister and checked for obvious cracks or split hoses etc.. The cost to diagnose the P0456 Jeep code is 1.0 hour of labor. The auto repair&x27;s diagnosis time and labor rates vary by location, vehicle&x27;s make and model, and even your engine type. Most auto repair shops charge between 75 and 150 per hour. The P0456 code on all vehicles is a very small emissions system leak. There are three main root causes 1) your gas cap 2) your canister close valve or 3) another leak that you&x27;ll need to conduct a. . Prep the holes you just drilled as follows a. Remove burrs from the edge with a file or sandpaper. b. Clean the hole with solvent and allow to completely dry. c. Applycover all bare metal with zinc-rich primer. d. Allow primer to dry for approximately 1 hour. Figure 5 5.