How do I fix P0171 system Too Lean bank 1?
You can usually fix P0171 using the following steps:
- Replace the fuel pump or fuel filter.
- Change the fuel pressure regulator.
- Replace the powertrain control module.
- Change one or more injectors.
- Replace one or more oxygen sensors.
- Change the mass airflow sensor.
- Repair vacuum leak.
What is code P0171 for Toyota Tacoma?
Oftentimes, a P0171 means that your Toyota is having trouble with a dirty or faulty mass airflow (MAF) sensor, or a vacuum leak downstream of the MAF sensor (perhaps in the PCV line or in the valve itself). Of course, this code can also signify a bad O2 sensor in bank 1.
What causes a lean condition on bank 1 and bank 2?
If you have codes stored in the engine computer for lean bank 1 and 2 is caused by the entire engine is running lean. This is caused by not enough fuel getting into the engine or too much unmetered air getting into the engine and the computer cannot compensate anymore to run it normal.
What causes fuel system too lean?
Most of the time, this happens due to faulty or dirty mass airflow sensors or weak fuel pumps. You may also find that jammed or unclean fuel filters or fuel injectors can cause unmetered air to enter the system and trigger any of these codes to set.
What repairs can fix the P0171 code?
To fix the P0171 code, you need to check and repair vacuum leaks, repair low fuel pressure, or replace any faulty sensor that can cause a lean mixture on bank 1.
Can a dirty air filter cause a P0171 code?
If the filter is clogged or excessively dirty, this is enough to impede or restrict the air flow, hence resulting in a lean running condition. Besides a dirty air filter, the P0171 code can also be blamed on a dirty or faulty MAF sensor and a clogged fuel filter.
What is Bank 1 too lean?
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 bad O2 sensor cause P0171?
When the ECM/PCM is having to add too much fuel based on input from the O2 sensor, the fault code P0171 will be sent to the ECM, which will trigger the check engine light to illuminate. This code could either mean that the oxygen sensor is detecting too much oxygen or too little fuel in the mixture.
Can bad gas cause a P0171 code?
Clogged fuel injectors or a dirty fuel filter will cause a similar backup. In cases where the vacuum system is leak-free, there is enough gas reaching the engine, and the code P0171 still shows with your check engine light, there remains a hope of finding the cause.