How do I fix error code P0171?

What repairs can fix the P0171 code?

  1. Replacing the fuel pump.
  2. Replacing the fuel filter.
  3. Replacing the fuel pressure regulator.
  4. Replacing the powertrain control module.
  5. Replacing one or more injectors.
  6. Replacing one or more oxygen sensors.
  7. Replacing the mass air flow sensor.
  8. Repairing a vacuum leak.

What does P0171 Bank 1 system Too Lean Mean?

The OBDII trouble code P0171 – System Too Lean (Bank 1) means that the engine air-fuel mixture is too lean, or there is too much air and too little fuel. Driving a car with the code P0171 can cause more damage to the engine over time, as when the engine runs lean, the combustion temperature is higher.

Can a PCV valve cause P0171?

The most common causes of the P0171 code are vacuum or intake leaks, low fuel pressure, faulty PCV valve, or a faulty MAF sensor. Other things can also cause the P0171 code.

Can PCV cause P0171?

Can Pcv Cause P0171? A leaking PCV hose could cause lean codes in the Ford Expedition. A vacuum leak is the most likely cause of a check engine light on and a P0171 and P0174 code stored in the car.

What does p0171 mean on a Ford?

System too lean (Bank 1). What Does P0171 Mean For Your Ford? Combustion engines run most efficiently when they maintain an air-fuel mixture ratio of 14.7 parts air to 1 part fuel. When there are more than 14.7 parts air to 1 part fuel in the air-fuel mixture, a lean condition exists and code P0171 is triggered.

What causes a p0171 O2 sensor to go bad?

If the P0171 is combined with the P0174 code, the problem is likely caused by an intake leak or the Intake Plenum Gasket and seals. If there are no intake leaks, the next step is to replace the air filter and clean the airflow meter. If the problem persists, the front oxygen (O2) sensor may need to be replaced.

What causes a Ford Expedition to misfire?

Misfire – If the air fuel mixture has gotten too far from factory specs, this can cause the Expedition to misfire. Idle Issues – With the air/fuel mixture altered, the vehicle can idle erratically as the computer compensates to keep the engine running.