why does my Acura MDX YF3 (2022-Present) engine misfire at idle

Symptoms

• Rough idle or engine shaking
• Check Engine Light (CEL) illuminated
• Decreased fuel efficiency
• Possible loss of power during acceleration
• Increased exhaust emissions or unusual smells

Diagnostic Steps

1. Scan for Error Codes

   • Use an OBD-II scanner to check for any stored trouble codes that can pinpoint the cause of the misfire. Look for codes such as P0300 (random/multiple cylinder misfire), P0301, P0302, etc.

2. Inspect Spark Plugs and Ignition Coils

   • Remove the spark plugs and inspect them for signs of wear, fouling, or damage. Check the ignition coils for cracks or carbon tracking.

3. Check Fuel System

   • Test the fuel pressure using a fuel pressure gauge to ensure it meets manufacturer specifications. Inspect the fuel injectors for clogs or leaks.

4. Examine Engine Vacuum

   • Use a vacuum gauge to check for any vacuum leaks. Listen for hissing sounds around hoses, gaskets, or the intake manifold.

5. Verify Engine Compression

   • Perform a compression test on each cylinder to ensure they are within the specified range. Low compression can indicate internal engine issues.

6. Inspect for Software Updates

   • Check if there are any available updates for the engine control unit (ECU) that may address the misfire issue.

Repair Instructions

1. Replace Faulty Spark Plugs or Ignition Coils

   • Tools Required: Socket set, torque wrench, spark plug socket.
   • Remove the engine cover (if applicable).
   • Disconnect the ignition coils from the harness and remove them using the socket set.
   • Replace spark plugs with OEM or equivalent parts.
   • Reinstall the ignition coils and ensure they are securely connected.

2. Clean or Replace Fuel Injectors

   • Tools Required: Fuel injector cleaning kit or replacement injectors, safety goggles, gloves.
   • If cleaning, use a fuel injector cleaning kit according to the manufacturer's instructions. If replacing, disconnect fuel lines and electrical connectors, and install new injectors.

3. Fix Vacuum Leaks

   • Tools Required: Vacuum gauge, hose clamps, replacement hoses.
   • Identify the source of the leak and replace the damaged hoses or gaskets. Use clamps to secure the hoses properly.

4. Perform Compression Test

   • Tools Required: Compression tester.
   • Remove spark plugs and insert the compression tester into each cylinder. Crank the engine and record the readings. Compare to specifications.

Estimated Time for Repair

• Total Time: Approximately 2-4 hours, depending on the issue identified and the components involved.

Safety Warnings

• Always disconnect the negative battery terminal before working on electrical components.
• Use protective eyewear and gloves when handling fuel and engine parts.
• Ensure the engine is cool before beginning any repairs to avoid burns.