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Evaporative Emissions System: Service Precautions

Fuel Cap Warning Message

The PCM detects whether the fuel fill cap is loose or missing under certain conditions and alerts the driver by showing the information in the odometer/outside temperature display. If the PCM detects a small volume leak, the MIL may come on during the second drive cycle and store a DTC.




First drive cycle

During the first drive cycle after a cold start, the PCM alerts the driver to check the fuel fill cap by showing a "CHECK FUEL CAP" message in the odometer/outside temperature display (A), and it stores Temporary DTC P0457 "Evaporative Emission (EVAP) System Leak Detected/Fuel Cap Loose or Missing". Tightening the fuel cap does not make the message go off immediately.

To make the message go off

Tighten the fuel fill cap three clicks, and do this procedure several times.

1. Turn the ignition switch OFF.
2. Start the engine, and drive at a steady speed over 28 mph (45 km/h), without moving the accelerator pedal, for about 1 minute.

Second drive cycle

During the second drive cycle after a cold start, if the fuel fill cap is still loose or missing, the PCM alerts the driver to check the fuel fill cap by showing a "CHECK FUEL CAP" message in the odometer/outside temperature display as same as the first drive cycle. Tightening the fuel cap does not make the message go off immediately.




Third drive cycle

During the third drive cycle after a cold start, if the fuel fill cap is still loose or missing, the PCM stores DTC P0457 "Evaporative Emission (EVAP) System Leak Detected/Fuel Cap Loose or Missing". The malfunction indicator lamp (MIL) (A) comes on, and the "CHECK FUEL CAP" message goes off.