my Ram 1500 DT (2019-Present) has a P0171 code, what should I do?

Solution

1. Preparation

• Ensure the vehicle is parked on a level surface and the engine is cool.
• Gather tools and parts needed for the repair.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to identify any vacuum leaks while the engine is running.
  3. Replace any damaged hoses or gaskets found during the inspection.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Disconnect the electrical connector from the MAF sensor.
  2. Remove the MAF sensor using a socket set (usually Torx or Phillips screws).
  3. Clean the MAF sensor using MAF cleaner; do not touch the sensor element directly.
  4. Allow the sensor to dry completely, then reinstall it and reconnect the electrical connector.

4. Test and Repair Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail’s test port.
  2. Start the engine and monitor the fuel pressure; it should match the manufacturer’s specifications (usually between 55-60 PSI).
  3. If pressure is low, check the fuel pump, fuel filter, and fuel injectors for issues.
  4. Replace any faulty components identified during the testing.

5. Inspect Oxygen Sensors

• Sub-steps:
  1. Locate the upstream oxygen sensor(s) in the exhaust system.
  2. Use a multimeter to check the voltage output; it should fluctuate between 0.1V and 0.9V.
  3. If the sensor is not functioning correctly, replace it with a new one, ensuring to use the correct part for your model.