Q: How to Replace the Canister Purge Valve,Fuel Tank Vent Valve and Vapor Canister in Subaru Outback?A: First of all, to replace the purge control solenoid valve, found under the intake manifold or on a bracket, you can disconnect the negative battery terminal and remove hoses and electrical connectors before reinstallation. The EVAP canister is replaced by disconnecting and reconnecting hoses and connectors. Also, the drain filter and valve, part of the canister in newer models, follow a similar replacement process. Replacing the fuel tank pressure sensor and the vent valve involves removing the fuel tank. The pressure control solenoid valve, situated above the rear axle differential or below the EVAP canister, requires disconnection of its connector and hoses. Installation is the reverse of removal.