Code result
P04E1
Crankcase Ventilation Hose Connection Sensor Circuit
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Open in sensor circuit
highOne of the most commonly reported causes for this code — check this first.
Related help
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