Diagnostic Aids

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Perform this test only when directed by QUICK TEST. DTC P0442 will set when EVAP control system monitor fails when PCM detects one of the following from EVAP system:

Less Than 2.5 in. H2O (.625 kPa) Bleed-Up In 15 Seconds At 75 Percent Fuel Fill
Vapor Generation Limit; More Than 2.5 in. H2O (.625 kPa) In 120 Seconds

DTC P0456 will set when a fuel vapor leak from an opening as small as 0.020" (0.508 mm).

If DTC P0457 is set, check for missing or leaking fuel filler cap.