Trouble Code P0300 and P0304 represent engine misfires. P0300 indicates a "general" engine misfire. OBD II P0304 indicates cylinder number 4 experienced a misfire.
Trouble Code P0455 indicates an EVAP system large pressure loss. A common cause for this code is loose or failing gas cap. The Evaporative Emission (EVAP) System is stores fuel vapors to stop fuel from escaping into the atmosphere. The EVAP system consists of the EVAP canister, the fuel tank pressure (FTP) sensor, EVAP lines and hoses, an EVAP canister purge solenoid valve which is normally closed, an EVAP service port, EVAP canister vent solenoid valve which is normally open, the fuel tank, and the engine control module (ECM).
Your Saturn Vue's engine control computer monitors the EVAP system for faults. The ECM also monitors the EVAP system for small and large leaks. During the EVAP code test, the ECM commands the EVAP canister vent solenoid valve ON. The ECM will lets the fuel tank pressure to drop for a length of time after which it turns OFF the EVAP canister purge solenoid valve. DTC P0455 sets when a required level of vacuum in the fuel tank can not be achieved due. The ECM translates this data into assuming the lack of vacuum is due to a large leak or leak within a vacuum source.
We recommend you contact the seller and express you concerns. You have the right to report the dealership to the DMV Investigators Office. You may also report the smog station which inspected this vehicle for suspicion of fraudulent smog checks. (800) 777-0133 DMV. (800) 952-5210 BAR.
posted by SmogTips Support