P04AD
EVAP System Purge Control Valve B Circuit High
Generic OBD-II
Common symptoms
What you'll notice
- Check the wiring and connections of the EVAP system purge control valve
- Inspect the EVAP canister and purge valve for any signs of damage or leaks
- Clean or replace the purge control valve if it appears to be faulty or contaminated
- Verify and ensure proper functionality of the EVAP system components, such as the canister vent valve or fuel tank pressure sensor.
Common causes
Most likely first
- Faulty or malfunctioning EVAP system purge control valve
- Broken or damaged wiring or connectors in the EVAP system purge control valve circuit
- Vacuum leak in the EVAP system, such as a cracked or disconnected hose
- Faulty or malfunctioning EVAP system pressure sensor
- Inadequate or incorrect fuel cap sealing, leading to excessive pressure in the EVAP system
How to diagnose & fix
Work through it in order
- Check engine light illuminated on the dashboard
- Difficulty starting the vehicle
- Decreased fuel efficiency
- Irregular idling or stalling of the engine
- Strong smell of fuel in the vehicle's cabin
Read & clear P04AD yourself
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