Reasons & Solutions Generic DTC of System Bank 1&2

Administrator posted this 07 May 2019

There is a list of trouble codes which help to identify problems with the supplement of the car. DTC can be divided into 4 types: Powertrain codes(P####), Body codes(B####), Chassis codes(C####) and Network Communication codes(U####), By the way, all of the can be grouped in generic or standard DTC and to Manufacturer or specific.

This article is about Generic DTC’s P0171, P0172, P0174, P0175 – which indicate faults with oxygen level in the fuel.

System Bank1 too rich - P0172 - low oxygen, rich fuel condition

System Bank1 too lean - P0171

System Bank2 too rich - P0175

System Bank2 too lean - P0174

This group of codes indicates errors in the transmission, namely the oxygen sensor indicators, which indicate the saturation of the fuel mixture with air.

All above-mentioned faults have after-effects, which you should pay attention and check the car with the app. So, for DTC’s P0175 and P0172, the most common symptom is a misfire. At low rates of exhaust in the air, it is difficult to detect the consequences, however: when driving the car stalls, disrupts the dynamics, a white residue appears on the candles.

As to DTC’s P0171 & P0174, you will find out that the car’s low power, black soot on the plugs will appear, also fuel consumption will increase. The faults can also cause a surge on acceleration.

So, there a few reasons, which can lead to faults.

1) The MAF (Mass Air Flow) Sensor is dirty or faulty (also it can be a result of usage of low-quality oil);

2) Failure in the vacuum system due to a weak valve, or the presence of cracks for leakage;

3) Reduced fuel pressure (more often as a consequence of the previous point);

When you see the problem, you won’t fill difficult to fix the problem. However, these errors should not be ignored, as they can lead to the fact that one day your car does not start at all, or suddenly stall.

Clear the error using the app inCarDoc. If the signal CheckEngine is still turned on, then you will have to find another solution depending on the problem, model and year of the car.