P0172 - SYSTEM TOO RICH (BANK 1)

The diagnostic code P0172 OBDII means that an O2 oxygen sensor in bank 1 found that there is not enough oxygen in the exhaust. Remember that in 6, 8- and 10-cylinder engines, bank 1 belongs to the part of the engine that has cylinder #1.

This DTC Code is very similar to code P0175, and your car may indicate both codes at the same time.

• It is likely that there is no problem when driving the vehicle.
• During engine start there are faults.

• It is likely that the MAF sensor is defective or dirty.
• Maybe the filter is dirty or have oil.
• There may be a vacuum leak.
• There are difficulties in fuel pressure.
• Fuel Pump Check Valve Failures.
• The PCV valve indicates a fault or a leak.
• EGR valve
• A flue gas leak is located before the lambda sensor.
• Leaks from The Evaporative Emission Control System

• Purify the MAF sensor and remember that it must be dry in order to install it, otherwise it could be damaged.
• Check the PCV valve and all vacuum hoses, and if there is any failure in these components, replace it.
• Check the fuel pressure.
• Verify the fuel pump.
• Fuel injectors should be cleaned if dirty.