Circuit Description

The EVAP control system checks for conditions that cause the EVAP system to purge continuously by commanding the canister vent solenoid on and EVAP solenoid off (canister vent solenoid closed and purge valve to zero percent duty cycle). If fuel tank vacuum level increases during the Service Bay Test, a continuous purge flow condition is indicates. A stuck open or leaking purge solenoid will cause this DTC to set.

DTC will also set when a continuous purge flow condition (fuel tank pressure is less than 2 volts) is detected during diagnostic test for 75 seconds and the following conditions are met:

• BARO greater than 75 kPa.
• Engine running.
• Both ECT and IAT are between 39-86°F (4-30°C) at engine start-up.
• Throttle angle at 7 and 35 percent.
• Vehicle speed less than 70 MPH.
• ECT not greater than 14°F (8°C) of IAT at start-up.
• Fuel tank between 15-85 percent.
• DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0452, P0453, P0502, P0503, P0601, P0602, P1133 and P1621 are not set.