Quick Reference Troubleshooting:

P0446:

A. Inspect the "Purge" circuit. Remove the canister purge valve and blow through it in both directions. The valve should not allow air to pass through it.

B. Inspect the "To Tank" circuit. Use the "Pressurize/Clamp/Observe" method to isolate the blockage by relocating the "test" hose closer each time to the DPS sensor.

C. Inspect the "Fresh Air" circuit. Use the "Pressurize/Clamp/Observe" method to isolate the blockage by disconnecting different points, each time farther from the canister in the "Fresh Air" circuit. Check the plastic fresh air tube in the frame rail for foreign material or moisture. Also remove the canister close valve and blow through it in both directions. The valve should allow air to pass through it without it being energized. Energize the valve with 12 volts, and then try to blow through it in both directions. The valve should not allow air to pass through it when energized. While blowing through the valve, release the 12 volts to determine if the valve opens immediately, or sticks closed. Replace the valve if it sticks closed.

P0441:

A. Inspect the "Purge" circuit. Remove the canister purge valve and blow through it in both directions. The valve should not allow air to pass through it.

P0455/P0442

A. Determine whether the leak is at the front or the rear of the car, and use the Evaporative System Schematic to isolate the leak in one circuit at a time by applying hose pinching pliers at different locations until the source of the leak is found.