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Home/Cars/Honda/Accord/8th Generation (2008-2012)/why does my Honda Accord 10th Generation (2018-2022) engine light keep coming on

why does my Honda Accord 10th Generation (2018-2022) engine light keep coming on

Honda Accord 8th Generation (2008-2012)

Severity: mediumDifficulty: mediumError Code: P04201-3 hours
3 min read
474 words

Problem Statement

Learn to diagnose and fix P0420 engine light issues in Honda Accord 10th Generation (2018-2022). Step-by-step guide with diagnostic and repair instructions.

Error Code
P0420
Component
Engine
Repair Time
1-3 hours

Safety Warnings

  • ⚠Disconnect battery before working on electrical systems.
  • ⚠Allow engine to cool before inspecting components under the hood.

Symptoms

  • •Check engine light illuminated
  • •Vehicle may experience rough idling
  • •Decreased fuel efficiency
  • •Engine stalling or misfiring
  • •Unusual noises from the engine
  • •Increased emissions

Diagnostic Steps

  1. 1Scan for error codes using an OBD-II scanner to determine the specific trouble codes.
  2. 2Check engine oil and coolant levels to ensure they are within the recommended range.
  3. 3Inspect the air filter for clogs or damage that could affect air intake.
  4. 4Examine the fuel cap for proper sealing and any signs of damage.
  5. 5Review the ignition system components (spark plugs, ignition coils) for wear or failure.
  6. 6Test the battery and charging system to ensure proper voltage and functionality.

Solution

Solution

1. Preparation

  • Gather necessary tools and parts.
  • Disconnect the negative terminal of the battery to ensure safety while working on the vehicle.

2. Address Trouble Codes

  • Sub-step 1: Based on the error codes retrieved, refer to a repair manual to identify the affected systems.
  • Sub-step 2: For a common P0420 code (Catalytic Converter Efficiency), inspect the exhaust system for leaks or damage.
  • Sub-step 3: If related to the ignition system, replace faulty spark plugs or ignition coils as necessary.

3. Replace Fuel Cap (if applicable)

  • Sub-step 1: Remove the old fuel cap by turning it counterclockwise.
  • Sub-step 2: Install a new fuel cap by turning it clockwise until it clicks into place.

4. Inspect and Clean Components

  • Sub-step 1: Remove the air filter housing and inspect the air filter. Replace if dirty.
  • Sub-step 2: Clean the Mass Air Flow (MAF) sensor using MAF cleaner if necessary.

5. Reconnect Battery and Clear Codes

  • Sub-step 1: Reconnect the negative terminal of the battery.
  • Sub-step 2: Use the OBD-II scanner to clear any stored error codes.

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
  • Socket set
  • Torque wrench
  • Screwdrivers
  • Air filter cleaner

Parts Required

  • Spark plugs (if needed)
  • Ignition coils (if needed)
  • Air filter
  • Fuel cap (if needed)

Additional Information

Error CodeP0420
Component

Engine

Repair Time

1-3 hours

Difficulty

medium

Severity

medium

Tools

5 items

Parts

4 items

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