why does my Toyota Highlander Third Generation (2014-2019) sputter on acceleration

Solution

1. Preparation

• Gather tools and materials: OBD-II scanner, fuel pressure gauge, socket set, multimeter, and cleaning supplies.
• Ensure the vehicle is parked on a flat surface and the engine is cool.

2. Replace Spark Plugs

• a. Remove Engine Cover: Use a socket set to remove screws and lift off the engine cover.
• b. Disconnect Ignition Coils: Unplug the electrical connectors from each ignition coil.
• c. Remove Ignition Coils: Unscrew the ignition coils and carefully pull them out.
• d. Remove Old Spark Plugs: Use a spark plug socket to carefully unscrew and remove old spark plugs.
• e. Install New Spark Plugs: Apply anti-seize compound to the threads of the new spark plugs and install them to the manufacturer's torque specification (typically around 13-16 lb-ft).
• f. Reinstall Ignition Coils: Place coils back, secure with screws, and reconnect electrical connectors.

3. Clean Throttle Body

• a. Access Throttle Body: Remove the air intake duct connected to the throttle body.
• b. Clean Throttle Body: Use throttle body cleaner and a soft brush to remove carbon buildup from the throttle plate and surrounding area. Ensure the throttle plate moves freely.
• c. Reassemble Intake Components: Reattach the air intake duct securely.

4. Check Fuel Delivery

• a. Connect Fuel Pressure Gauge: Locate the fuel rail pressure test port and connect the fuel pressure gauge.
• b. Turn Ignition ON: Without starting the engine, turn the ignition to the ON position to check fuel pressure readings.
• c. Compare with Specifications: Ensure the fuel pressure matches the manufacturer’s specifications (typically around 50-60 psi).
• d. Replace Fuel Filter (if necessary): If pressure is low, replace the fuel filter as per service schedule.