what does it mean if my Ram 1500 DT (2019-Present) has a P0171 code?

Solution

1. Preparation

• Tools Required: OBD-II scanner, basic hand tools, multimeter, fuel pressure gauge, MAF cleaner (if applicable).
• Disconnect the battery to ensure safety while working on the electrical system.

2. Inspect Air Intake System

• Sub-steps:
  • Visually inspect all air intake hoses and connections for cracks or loose fittings.
  • Use a smoke machine or soapy water to detect any vacuum leaks.
  • Replace any damaged hoses or gaskets as necessary.

3. Check Fuel Pressure

• Sub-steps:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "On" position without starting the engine to check the pressure reading.
  • Compare the reading to the specifications in the service manual; replace the fuel pump if pressure is low.

4. Clean or Replace MAF Sensor

• Sub-steps:
  • Detach the MAF sensor from the air intake.
  • Spray MAF cleaner onto the sensor element without touching it.
  • Reinstall the sensor and ensure all connections are secure.

5. Inspect Oxygen Sensors

• Sub-steps:
  • Use a multimeter to check the voltage output of the upstream oxygen sensor while the engine is running.
  • If the voltage is not fluctuating between 0.1V and 0.9V, replace the sensor.
  • Clear the P0171 code with the OBD-II scanner and take the vehicle for a test drive.

6. Inspect Fuel Injectors

• Sub-steps:
  • Remove the fuel rail with the injectors attached.
  • Check each injector for clogs and perform a cleaning if necessary.
  • Replace any malfunctioning injectors.