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.
2018 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE
Drive Cycle I
| DTC | Item | Condition |
|---|---|---|
| P0455 | EVAP SYSTEM (CPC) LEAK DETECTED (LARGE LEAK) | «Coolant Temp.»: 5 - 45°C (41 - 113°F) «IAT Sensor #11»: 5 - 50°C (41 - 122°F) |
| P0456 | EVAP SYSTEM (CPC) LEAK DETECTED (VERY SMALL LEAK) | |
| P04AF | EVAP SYSTEM PURGE CONTROL VALVE (CPC) "B" STUCK CLOSED | |
| P1451 | EVAP SYSTEM CLOG DETECTED (PIPE) | |
| P2402 | EVAP SYSTEM LEAK DETECTION PUMP CONTROL CIRCUIT HIGH | |
| P2404 | EVAP SYSTEM LEAK DETECTION PUMP SENSE CIRCUIT RANGE/PERFORMANCE | |
| P2420 | EVAP SYSTEM SWITCHING VALVE CONTROL CIRCUIT HIGH |
CAUTION:
Be careful of the state of the battery when performing the drive cycle I consecutively. Performing the drive cycle I consecutively without the engine running may cause a low battery voltage and battery discharge.
Factory Service Tools
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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