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Home/Cars/Subaru/Outback/5th Generation (2015-2019)/how to fix P0420 code on Tesla Outback 5th Generation (2015-2019)

how to fix P0420 code on Tesla Outback 5th Generation (2015-2019)

Subaru Outback 5th Generation (2015-2019)

Severity: highDifficulty: mediumError Code: P04202-4 hours
3 min read
506 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

Learn how to diagnose and fix P0420 exhaust system issue in Tesla Outback 2015-2019. Step-by-step guide with diagnostic procedures and repair instructions.

Error Code
P0420
Component
Exhaust System
Repair Time
2-4 hours

Safety Warnings

  • ⚠Disconnect the battery before working on electrical systems.
  • ⚠Allow the exhaust system to cool before handling components.

Symptoms

  • •Check engine light illuminated
  • •Decreased fuel efficiency
  • •Engine stalling or misfiring
  • •Unusual exhaust odors
  • •Rough idle

Diagnostic Steps

  1. 1Scan for error codes using an OBD-II scanner to confirm the P0420 code.
  2. 2Inspect the exhaust system for leaks, especially before and after the catalytic converter.
  3. 3Check the condition of the oxygen sensors using a multimeter to ensure they are functioning correctly.
  4. 4Visually inspect the catalytic converter for any physical damage or obstruction.
  5. 5Verify the fuel system pressure and ensure it is within specifications.
  6. 6Inspect for any vacuum leaks that may affect the air-fuel mixture.

Solution

Solution

1. Preparation

  • Gather tools and parts needed.
  • Disconnect the negative battery terminal to ensure safety during repairs.

2. Inspect and Replace Oxygen Sensors

  • Tools Required: O2 sensor socket, ratchet, torque wrench.
  • Sub-steps:
    1. Locate the upstream and downstream oxygen sensors.
    2. Disconnect the electrical connectors from both sensors.
    3. Remove the upstream sensor using the O2 sensor socket and ratchet.
    4. Install the new upstream sensor and torque it to the manufacturer's specification (typically 30-40 ft-lbs).
    5. Repeat the process for the downstream sensor if deemed necessary.

3. Check and Replace Catalytic Converter

  • Tools Required: Socket set, torque wrench, exhaust hanger removal tool.
  • Sub-steps:
    1. Remove any heat shields or components obstructing access to the catalytic converter.
    2. Unbolt the catalytic converter from the exhaust system using the socket set.
    3. Inspect the mounting flange and gaskets; replace if degraded.
    4. Install the new catalytic converter, ensuring proper alignment.
    5. Torque the bolts to the manufacturer’s specifications (usually around 25-30 ft-lbs).

4. Reassemble and Reconnect Battery

  • Reinstall any heat shields or components removed during the repair.
  • Reconnect the negative battery terminal securely.

Verification

After completing the repair, verify that the issue has been resolved:

  • Test the affected component to ensure it functions correctly
  • Check for any error codes or warning lights
  • Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • OBD-II scanner
  • O2 sensor socket
  • Ratchet
  • Torque wrench
  • Socket set
  • Exhaust hanger removal tool
  • Multimeter

Parts Required

  • Upstream oxygen sensor
  • Downstream oxygen sensor (if applicable)
  • Catalytic converter (if replacement is necessary)
  • Exhaust gaskets

Additional Information

Error CodeP0420
Component

Exhaust System

Repair Time

2-4 hours

Difficulty

medium

Severity

high

Tools

7 items

Parts

4 items

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