P04E1

Crankcase Ventilation Hose Connection Sensor Circuit

Moderate severity

A dedicated sensor monitors whether the PCV hose is fitted to its connector at the engine. The ECU detects a circuit fault on this sensor - cannot determine whether the hose is connected. Required by some emissions regulations to flag a disconnected PCV hose immediately.

Common causes

Open in sensor circuit
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $70-280
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P04E1 mean?

P04E1 means "Crankcase Ventilation Hose Connection Sensor Circuit". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P04E1?

open in sensor circuit — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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