my Toyota Corolla E210 (2019-2024) has a rough start in the morning, what’s wrong?

Solution

1. Preparation

• Gather tools and materials.
• Park the vehicle on a level surface, engage the parking brake, and disconnect the battery.

2. Inspect and Replace Spark Plugs

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil cover if applicable.
• Remove the spark plug wires or ignition coils.
• Use a spark plug socket to remove the old spark plugs.
• Inspect the old spark plugs for wear; replace with OEM specifications.
• Torque the new spark plugs to the manufacturer's specified value (typically 13-15 ft-lbs).

3. Check and Replace Fuel Filter (if applicable)

• Tools Required: Fuel line disconnect tool, wrench set, container for fuel spill.
• Relieve fuel system pressure by removing the fuel pump fuse and starting the engine until it stalls.
• Locate the fuel filter and disconnect the inlet and outlet fuel lines.
• Install the new fuel filter, ensuring the correct flow direction is observed.
• Reconnect the fuel pump fuse and prime the fuel system by turning the ignition on without starting.

4. Address Battery Condition

• Tools Required: Multimeter, battery terminal cleaner.
• Check the battery voltage with a multimeter; it should be above 12.4 volts.
• Clean battery terminals and ensure all connections are tight.
• If the battery is weak (below 12.4 volts), consider replacing it.

5. Inspect Air Filter

• Tools Required: Screwdriver or ratchet set (if necessary for housing).
• Open the air filter housing and remove the air filter.
• Inspect for dirt and debris; replace if it appears clogged or dirty.
• Reassemble the air filter housing securely.