what causes my Toyota Highlander Fourth Generation (2020-present) to stall while driving

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure safety while working on the electrical components.

2. Fuel System Inspection

• Tools Required: Fuel pressure gauge, wrenches, replacement fuel filter if needed.
• Check fuel pressure using the fuel pressure gauge; it should meet the specifications in the service manual.
• If pressure is low, inspect the fuel pump and replace if necessary.
• Replace the fuel filter if it is clogged or has not been changed according to maintenance schedule.

3. Vacuum Leak Repair

• Tools Required: Hose clamps, vacuum hose replacement if needed.
• Visually inspect all vacuum hoses for cracks or disconnections.
• Replace any damaged hoses and ensure all connections are tight.

4. Sensor Testing

• Tools Required: Multimeter, MAF sensor cleaner (if applicable).
• Disconnect the MAF and TPS connectors; test the sensors for proper voltage and resistance using the multimeter.
• Clean the MAF sensor with MAF cleaner to ensure accurate readings.
• Replace any faulty sensors based on testing results.

5. Ignition System Check

• Tools Required: Spark plug socket, torque wrench, replacement spark plugs and ignition coils if needed.
• Inspect spark plugs for wear and carbon buildup; replace if necessary.
• Check ignition coils for proper operation; replace any faulty coils.
• Torque new spark plugs to manufacturer specifications.

6. Electrical System Testing

• Tools Required: Multimeter.
• Check battery voltage and load test the battery; replace if it fails.
• Test alternator output; ensure it meets the specifications and replace if underperforming.