P1091 – Subaru OBD-II 1996 & Newer models DTC

Subaru OBD-II 1996 & Newer models DTC P1091 – Tumble generator valve #1 (RH) malfunction (stuck close)

DTC P1091 meaning on Subaru OBD-II 1996 & Newer models

DTC P1091 indicates a malfunction related to the Tumble Generator Valve #1 (RH) on Subaru vehicles equipped with OBD-II systems from 1996 onwards.

Subaru OBD-II 1996 & Newer models DTC P1091 symptoms

  • Check Engine Light (CEL) illuminated on the dashboard
  • Reduced engine performance
  • Possible rough idling or stalling

Subaru OBD-II 1996 & Newer models DTC P1091 causes

  • Tumble Generator Valve #1 (RH) stuck in the closed position
  • Wiring or connector issues related to the Tumble Generator Valve
  • Faulty Tumble Generator Valve #1 (RH)

Subaru OBD-II 1996 & Newer models DTC P1091 seriousness

The seriousness of DTC P1091 lies in its potential to affect engine performance and emissions. Ignoring this code can lead to decreased fuel efficiency and potential engine damage over time.

How to diagnose DTC P1091 on Subaru OBD-II 1996 & Newer models

  • Use an OBD-II scanner to retrieve the specific fault code
  • Inspect the Tumble Generator Valve #1 (RH) for any physical obstructions or signs of damage
  • Check the wiring and connectors associated with the Tumble Generator Valve for any issues

How to fix DTC P1091 on Subaru OBD-II 1996 & Newer models

  • Clean or replace the Tumble Generator Valve #1 (RH) if stuck or faulty
  • Repair any damaged wiring or connectors related to the Tumble Generator Valve
  • Clear the fault code and reset the Check Engine Light after completing repairs

How to erase DTC P1091 on Subaru OBD-II 1996 & Newer models

  • Use an OBD-II scanner to clear the stored fault code
  • Alternatively, disconnect the vehicle’s battery for a few minutes to reset the ECU and clear the code

Recommended tools for Subaru OBD-II 1996 & Newer models diagnostics

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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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