Engine-Codes - Subaru - P1086 SUBARU

P1086 SUBARU - Tumble Generated Valve Position Circuit Low Sensor 2

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

P1086 SUBARU Possible Causes

  • Faulty Tumble Generator Position Sensor
  • Tumble Generator Position Sensor harness is open or shorted
  • Tumble Generator Position Sensor circuit poor electrical connection
  • Faulty Tumble Generator Valve
  • Faulty Engine Control Module (ECM)

How is the P1086 SUBARU code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the P1086 SUBARU code

Labor: 1.0

The cost to diagnose the P1086 SUBARU code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P1086 SUBARU Meaning

The tumble generator system uses an electronically controlled butterfly valve in each intake runner port. At cold idle, the tumble generator system will redirect the air charge through a different port. These ports have a finish characteristic that causes the air/fuel mixture to swirl and tumble greatly and create better combustion. This results in greater idle quality, cleaner emissions, and easier cold-starts.
Once the vehicle warms up, the tumble generator system will be deactivated and the intake air charge will be directed through the standard intake ports.
The tumble generator sensor is responsible for measuring the position of the tumble generator butterfly valves. As the butterfly valves are opened or closed, signal voltage will vary accordingly at the position sensor.
The Diagnostic Trouble Code (DTC) will set when the ECM detects a low voltage signal from the tumble generator valve position sensor.

More Information

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