DTC P2421: Notes
DTC P2421 : Evaporative Emission (EVAP) Canister Vent Shut Valve Stuck Open
Special Tools Required
Pump/Gauge, 0-30 inHg Snap-on YA4000B or equivalent, commercially available
Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B
How to use this service information .
NOTE:
- Before you troubleshoot, review the How to Troubleshoot - Refer to: How to Troubleshoot the CVT System or How to Troubleshoot the Fuel and Emissions Systems .
- The fuel system is designed to allow specified maximum vacuum and pressure conditions. Do not deviate from the vacuum and pressure tests as indicated in these procedures. Excessive pressure/vacuum would damage the EVAP components or cause eventual fuel tank failure.
NOTE:
Fresh fuel has a higher volatility that will create greater pressure/vacuum. The best condition for testing is less than a full tank of fresh fuel. If possible, to assist in leak detection, add 1 gallon of fresh fuel to the tank (as long as it will not fill the tank), just before starting these procedures.