Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Typical Malfunction Thresholds
"Saturated" indicates that the EVAP pressure change is less than 0.75 mmHg (0.1 kPa) in 30 seconds.
| One of following conditions met | - |
| FTP when 4 seconds after reference pressure measurement began | More than -7.5 mmHg (-1 kPa) |
| Reference pressure | Less than -36.4 mmHg (-4.85 kPa) |
| Reference pressure | -7.9 mmHg (-1.057 kPa) or more |
| Reference pressure | Not saturated |
| Reference pressure difference between first and second | 5.3 mmHg (0.7 kPa) or more |
- P0450: Pressure sensor chatteringTYPICAL MALFUNCTION THRESHOLDS - P0450: PRESSURE SENSOR CHATTERING
EVAP pressure Less than 42.11 kPa (316 mmHg) or more than 123.761 kPa (928 mmHg) - P0451: Pressure sensor noiseTYPICAL MALFUNCTION THRESHOLDS - P0451: PRESSURE SENSOR NOISE
Pressure variation indicated by pressure sensor in 10 seconds More than +/- 0.3 kPa (+/- 2.25 mmHg) 10 times - P0451: Pressure sensor stuckTYPICAL MALFUNCTION THRESHOLDS - P0451: PRESSURE SENSOR STUCK
0.02 inch leak pressure variation indicated by pressure sensor in 10 seconds Less than 0.65 kPa (4.87 mmHg) - P0452: Pressure sensor low voltageTYPICAL MALFUNCTION THRESHOLDS - P0452: PRESSURE SENSOR LOW VOLTAGE
EVAP pressure Less than 42.11 kPa (316 mmHg) - P0453: Pressure sensor high voltageTYPICAL MALFUNCTION THRESHOLDS - P0453: PRESSURE SENSOR HIGH VOLTAGE
EVAP pressure More than 123.761 kPa (928 mmHg)
"Saturated" indicates that the EVAP pressure change is less than 0.75 mmHg (0.1 kPa) in 30 seconds.
P0455: EVAP gross leak
| FTP when vacuum introduction complete | Higher than reference pressure x 0.2 |
P0456: EVAP small leak (0.02 inch leak)
| FTP when vacuum introduction was complete | Between 1 and 2 |
| Condition 1. | Higher than second reference pressure |
| Condition 2. | Lower than reference pressure x 0.2 |
| Atmospheric pressure (absolute pressure) | 70 kPa (525 mmHg) or more, and less than 110 kPa (825 mmHg) |
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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