why does my Toyota Camry have a rough idle when I stop

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, screwdrivers, throttle body cleaner, multimeter, vacuum gauge.
• Allow the engine to cool before starting work.
• Disconnect the battery to ensure safety while working on electrical components.

2. Clean Throttle Body

• Steps:
  1. Remove the air intake duct connected to the throttle body using a socket set.
  2. Disconnect the electrical connector from the throttle body.
  3. Use throttle body cleaner and a soft cloth to clean the throttle plate and surrounding areas.
  4. Reconnect the electrical connector and reinstall the air intake duct, ensuring all clamps are tight.

3. Inspect and Test Idle Air Control Valve

• Steps:
  1. Locate the IAC valve, usually mounted on the throttle body.
  2. Remove the IAC valve using a socket set.
  3. Inspect for carbon buildup; clean if necessary with throttle body cleaner.
  4. Test the IAC valve operation with a multimeter according to specifications (consult service manual for specific values).
  5. Replace the IAC valve if it is faulty.

4. Check for Vacuum Leaks

• Steps:
  1. Inspect all vacuum lines for cracks, breaks, or loose connections.
  2. Use a vacuum gauge to check system integrity; a reading outside the normal range indicates a leak.
  3. Replace any damaged vacuum lines or reattach loose connections.

5. Verify Fuel Pressure

• Steps:
  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the "On" position without starting the engine to check the fuel pressure.
  3. Compare the reading to the manufacturer specifications; replace the fuel pump or filter if pressure is low.