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.
On Board Diagnosis Logic
NOTE: If DTC P0451 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. P0463
P0451:
DTC Confirmation Procedure
NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
WITH SDT
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and wait at least 40 seconds.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to [P0451 EVAP Control System Pressure Sensor].
NOTE: Do not depress accelerator pedal even slightly.
WITH GST
Follow the procedure "WITH SDT" above.
Diagnosis Procedure
Step 1:
Step 2-4:
Component Inspection
EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Remove EVAP control system pressure sensor with its harness connector. Always replace O-ring 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.