my Honda Civic 10th Generation (2016-2021) engine stalls when stopped what could be wrong

Solution

1. Preparation

• Gather tools and parts.
• Ensure the engine is cool and disconnect the negative battery terminal.
• Tools required: OBD-II scanner, socket set, screwdriver set, vacuum gauge.

2. Clean the Idle Air Control Valve (IACV)

• Remove the IACV from the throttle body.
  • Use a socket or screwdriver to remove mounting screws or bolts.
• Clean the valve with throttle body cleaner.
  • Spray cleaner into the valve and wipe it clean with a lint-free cloth.
• Reinstall the IACV to the throttle body, tightening screws to the manufacturer’s torque specifications.

3. Clean the Throttle Body

• Remove the throttle body from the intake manifold.
  • Disconnect electrical connectors and vacuum hoses.
  • Use a socket set to remove mounting bolts.
• Clean the throttle body interior with throttle body cleaner.
  • Ensure the throttle plate and surrounding areas are free of carbon deposits.
• Reinstall the throttle body and reconnect all components securely.

4. Test Fuel Pressure

• Locate the fuel pressure test port on the fuel rail.
• Attach the fuel pressure gauge to the test port.
• Start the engine and observe the fuel pressure reading.
  • Compare the reading to manufacturer specifications (typically around 40-50 psi).
• If pressure is low, inspect the fuel pump and filter for issues.

5. Inspect Ignition System

• Remove spark plugs using a socket set for inspection.
• Check for signs of wear, fouling, or damage on the spark plugs.
• Replace spark plugs if they are worn beyond specification (typically every 30,000-60,000 miles).
• Test ignition coils for proper functionality using a multimeter.