how to solve the P0174 code on my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum leak detector or spray bottle with soapy water.
• Steps:
  1. Inspect all vacuum hoses for cracks or disconnections.
  2. Use a vacuum leak detector or spray soapy water around suspected areas; bubbles indicate a leak.
  3. Replace any damaged hoses or reattach disconnected ones.

3. Clean the MAF Sensor

• Tools Required: MAF sensor cleaner, soft cloth.
• Steps:
  1. Locate the MAF sensor within the air intake duct.
  2. Disconnect the sensor electrical connector.
  3. Remove the MAF sensor from its housing.
  4. Spray the MAF sensor with MAF cleaner and let it dry completely before reinstalling.

4. Test the Fuel System

• Tools Required: Fuel pressure gauge.
• Steps:
  1. Locate the fuel rail test port.
  2. Attach the fuel pressure gauge to the test port.
  3. Turn the ignition key to the "ON" position (do not start engine) and check fuel pressure against manufacturer specifications.
  4. If pressure is low, inspect the fuel pump and filter for issues.

5. Inspect Throttle Body and Intake Manifold

• Tools Required: Throttle body cleaner, soft cloth.
• Steps:
  1. Remove the air intake duct from the throttle body.
  2. Inspect the throttle body for carbon buildup.
  3. Clean the throttle body using throttle body cleaner and a soft cloth.
  4. Check the intake manifold gasket for any signs of wear or leaks, replacing if necessary.

6. Reassemble and Finalize

• Reconnect all components removed during the repair.
• Reconnect the negative battery terminal.
• Clear the P0174 code using the OBD-II scanner.