my Toyota Corolla E140 (2006-2013) has a check engine light and rough idle what to do

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool down before starting work.

2. Scan and Clear Codes

• Use an OBD-II scanner to retrieve and note any error codes.
• Clear the error codes and take the vehicle for a short drive to see if the code reappears.

3. Inspect Spark Plugs and Ignition Coils

• Remove the engine cover if necessary.
• Use a socket set to remove spark plugs and inspect their condition (look for wear or carbon buildup).
• Replace any faulty spark plugs and check ignition coils for proper operation, replacing as needed.

4. Clean Throttle Body and Idle Air Control Valve

• Remove the intake duct to access the throttle body.
• Use throttle body cleaner to spray and wipe down the throttle plate and surrounding area.
• Remove the idle air control valve if accessible, clean it with appropriate cleaner, and reinstall.

5. Check Fuel System

• Connect a fuel pressure gauge to the fuel rail to measure the pressure.
• Compare the reading to the manufacturer specifications; replace the fuel pump if pressure is low.
• Inspect the fuel filter and replace it if it is clogged.

6. Inspect Vacuum Hoses

• Visually check all vacuum hoses connected to the intake manifold and other components.
• Replace any cracked or damaged hoses to restore proper vacuum levels.