The P0172 trouble code indicates that the air-fuel mixture is too rich in bank 1. This code typically points to issues related to the engine receiving too much fuel or too little air, leading to potential operational problems or damage to the engine components.
System Too Rich (Bank 1)
Code symptoms P0172.
1. Decreased fuel efficiency.
2. Black smoke from the exhaust.
3. Malfunction indicator light (MIL) illumination.
This code is common in brands such as:: Chevrolet, Renault, Ford, Toyota, Nissan, Mercedes Benz, Honda.
Causes of the code P0172.
1. Faulty oxygen (O2) sensor.
2. Issues with the fuel pressure regulator.
3. Problems with the fuel injectors.
Code Solutions P0172.
1. Replace the oxygen (O2) sensor if it is faulty.
2. Check and ensure proper function of the fuel pressure regulator.
3. Inspect and clean or replace the fuel injectors if necessary.