how to fix P0171 code in Volkswagen Tiguan First Generation (2007-2018)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery negative terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Sub-steps:

  1. Remove the engine cover (if applicable) using a socket set.
  2. Inspect all vacuum hoses for cracks or disconnections; replace any damaged hoses.
  3. Check the intake manifold gasket for leaks; replace if necessary.

• Tools Required:

  • Socket set
  • Screwdrivers

3. Examine and Clean MAF Sensor

• Sub-steps:

  1. Disconnect the MAF sensor connector.
  2. Remove the MAF sensor from the air intake duct.
  3. Clean the MAF sensor with MAF cleaner spray, avoiding contact with the sensor elements.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

• Tools Required:

  • Torx or socket set (to remove MAF)
  • MAF sensor cleaner

4. Clean Throttle Body

• Sub-steps:

  1. Remove the air intake hose connected to the throttle body.
  2. Use throttle body cleaner to clean the throttle plate and surrounding area.
  3. Reinstall the intake hose securely.

• Tools Required:

  • Throttle body cleaner
  • Screwdrivers or socket set

5. Test Fuel Pressure

• Sub-steps:

  1. Locate the fuel rail and connect the fuel pressure gauge to the service port.
  2. Turn the ignition to the "ON" position (do not start) to check fuel pressure.
  3. Compare the reading to the manufacturer’s specifications; replace the fuel pump or filter if pressure is low.

• Tools Required:

  • Fuel pressure gauge

6. Check Fuel Injectors

• Sub-steps:

  1. Disconnect the fuel injector connectors.
  2. Use a multimeter to test the resistance of each injector; replace any that are out of specification.
  3. Clean injectors with a fuel injector cleaner or replace if clogged or leaking.

• Tools Required:

  • Multimeter
  • Fuel injector cleaner