P04E4
Crankcase Ventilation Hose Connection Sensor Circuit Intermittent/Erratic
Generic OBD-II
Common symptoms
What you'll notice
- Inspect and clean the crankcase ventilation hose connection sensor
- Replace or repair the crankcase ventilation hose connection sensor
- Check and fix any loose connections or damaged wiring related to the sensor circuit
- Update or reprogram the vehicle's engine control module (ECM)
- Conduct a thorough inspection of the overall crankcase ventilation system and address any issues found
Common causes
Most likely first
- Incorrect installation or loose connection of the crankcase ventilation hose
- Faulty or malfunctioning sensor circuit
- Intermittent electrical connection issues within the sensor circuit
- Sensor circuit experiencing erratic behavior or fluctuations
- Sensor circuit encountering intermittent faults or errors during operation
How to diagnose & fix
Work through it in order
- Engine misfire or rough idle
- Decreased engine performance or power
- Check engine light (MIL) illuminated
- Irregular or erratic engine idling
- Excessive oil consumption
Read & clear P04E4 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.