my Renault Clio V (2019-Present) has a check engine light with P0171 code, what does it mean?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety.
• Set the vehicle on a flat surface and engage the parking brake.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses for cracks or disconnections.
  2. If any faulty hoses are found, replace them with OEM parts.
  3. Check the intake manifold gasket for leaks, replacing it if necessary.

3. Clean or Replace the MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, which is typically near the air filter box.
  2. Disconnect the electrical connector and remove the sensor.
  3. Clean the MAF sensor using MAF cleaner spray; do not touch the sensing element.
  4. Reinstall the MAF sensor and reconnect the electrical connector. If damaged, replace with a new sensor.

4. Check Fuel Pressure

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail's test port.
  2. Turn the ignition on (do not start the engine) and check the fuel pressure reading. It should be within the manufacturer's specifications.
  3. If pressure is low, inspect the fuel pump and fuel filter for blockages or failures.

5. Inspect and Test Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail with injectors attached (if necessary).
  2. Test each injector for proper spray pattern using a noid light or injector tester.
  3. Clean or replace any faulty injectors.

6. Reset and Test

• Sub-steps:
  1. Reconnect the battery.
  2. Clear the P0171 code using the OBD-II scanner.
  3. Start the engine and monitor for any returning codes or symptoms.