HAS ANYONE HAD A PROPLEM W/CHECK ENGINE CODE P0446 FOR 97 EXPLORER XLT? OBD-II SCAN TOOL I USED SAYS IT IS AN EVAPORATIVE EMISSION CONTROL SYSTEM VENT CONTROL CIRCUIT MALFUNCTION. CAN ANYONE EXPLAIN THIS? COULD IT BE THE VAPOR MGMT VALVE THAT IS HAS GONE BAD? I CHECKED ALL OF CONNECTIONS TO & FROM CANISTER.