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TuningBot DTC Database · v4.37.15

P1491 Subaru - Positive crankcase ventilation (PCV) - malfunction

Manufacturer-specific interpretation for Subaru. All interpretations of P1491

P · PowertrainEngineOBD2

What P1491 means

P1491
Positive crankcase ventilation (PCV) - malfunction Subaru · engine Data confidence 62%

The control module detected improper operation of the Positive crankcase ventilation (PCV). This is the manufacturer-specific definition used by Subaru.

Possible causes

  • Wiring
  • hose blocked/leaking

Related and nearby codes

How to read P1491

P

Powertrain: engine, transmission and driveline systems.

1

Manufacturer-defined range: the meaning can differ between brands.

491

Specific fault index within the subsystem.

Frequently asked questions about P1491

What does P1491 mean?

Positive crankcase ventilation (PCV) - malfunction. The control module detected improper operation of the Positive crankcase ventilation (PCV). This is the manufacturer-specific definition used by Subaru.

Is P1491 generic or manufacturer-specific?

P1491 is a manufacturer-specific code. In this database it is documented for: Subaru. The same number can mean something different on other brands.

Can TuningBot remove P1491 at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

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