how to fix P0174 code on my Toyota RAV4 Fourth Generation (2013-2018)?

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the battery to ensure safety.
• Allow the engine to cool before starting work.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all vacuum hoses for cracks or disconnections.
  2. Remove the air intake duct and inspect the intake manifold for leaks.
  3. Replace any damaged hoses or gaskets found during inspection.
• Tools Required: Screwdriver set, pliers.

3. Fuel System Check

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Start the engine and observe the pressure reading; it should be within the specified range (usually 30-40 psi for a RAV4).
  3. If pressure is low, inspect the fuel pump and replace if necessary.
  4. If pressure is adequate, check the fuel injectors for clogs or leaks and clean or replace them if needed.
• Tools Required: Fuel pressure gauge, injector cleaning kit.

4. MAF Sensor Cleaning/Replacement

• Sub-steps:
  1. Locate the MAF sensor in the intake system.
  2. Disconnect the electrical connector and remove the sensor.
  3. Clean the MAF sensor using MAF cleaner spray; avoid touching the sensor elements.
  4. If the sensor is damaged, replace it with a new one.
  5. Reinstall the MAF sensor and reconnect the electrical connector.
• Tools Required: MAF cleaner spray, Torx screwdriver.

5. Oxygen Sensor Inspection

• Sub-steps:
  1. Locate bank 2 oxygen sensor (usually after the catalytic converter).
  2. Disconnect the sensor's electrical connector.
  3. Use a multimeter to check the sensor's voltage output while the engine is running.
  4. If readings are outside the manufacturer specifications, replace the oxygen sensor.
• Tools Required: Multimeter, oxygen sensor socket.