P0451
P0451 EVAP Control System Pressure SensorComponent Description
The EVAP control system pressure sensor (2) detects pressure in the purge line. The sensor output voltage to the ECM increases as pressure increases.
- EVAP canister vent control valve (1)
- Drain filter (3)
- EVAP canister (4)
- White arrow indicates Vehicle front
On Board Diagnosis Logic
If DTC P0451 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
P0451:
DTC Confirmation Procedure
1. If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and wait at least 40 seconds.
NOTE: Do not depress accelerator pedal even slightly.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to [P0451 EVAP Control System Pressure Sensor].
Diagnosis Procedure
Step 1-4:
Component Inspection
EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister.
Do not reuse the O-ring, replace it with a new one.
2. Install a vacuum pump to EVAP control system pressure sensor.
3. Turn ignition switch ON and check output voltage between ECM terminal 32 and ground under the following conditions.
CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Never apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/cm2, 14.69 psi).
4. If NG, replace EVAP control system pressure sensor.