my Toyota Tacoma N300 (2016-Present) shows a P0171 code, what does it mean

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical short circuits.
• Ensure the engine is cool before starting work.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all air intake hoses for cracks or loose connections.
  2. Tighten any loose clamps and replace damaged hoses as needed.
  3. If leaks are found, replace the affected components.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, usually situated between the air filter and throttle body.
  2. Remove the MAF sensor carefully using a Torx screwdriver.
  3. Clean the sensor with MAF sensor cleaner; do not touch the sensor element.
  4. If cleaning does not resolve the issue, replace the MAF sensor with a new one.

4. Check Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail to measure fuel pressure.
  2. Compare the reading to manufacturer specifications (typically between 40-50 psi).
  3. If pressure is low, inspect the fuel pump and replace the fuel filter if clogged.

5. Inspect Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic converter) oxygen sensor.
  2. Use an O2 sensor socket to remove the sensor.
  3. Inspect the sensor for signs of wear or contamination; replace if necessary.
  4. Reinstall the new or cleaned sensor and reconnect the wiring harness.