OBD2 fault code

P0172 System too rich, bank 1

High priorityPowertrain (P)Generic code (SAE)

The engine control unit has detected a rich mixture in the first cylinder bank: too much fuel or too little air. This can lead to higher fuel consumption, black smoke and contamination of the catalytic converter.

Most common causes of P0172

1Dirty fuel injectors (excessive flow)
2Excessive fuel pressure due to a defective regulator
3Dirty air sensor or blocked air filter

Can I keep driving?

Have the fault checked at a garage within a few days, as the catalytic converter can be damaged if you continue to drive for long periods.

P0172 – frequently asked questions

What does fault code P0172 mean?+

P0172 means: System too rich, bank 1. The engine control unit has detected a rich mixture in the first cylinder bank: too much fuel or too little air. This can lead to higher fuel consumption, black smoke and contamination of the catalytic converter.

What are the most common causes of P0172?+

Dirty fuel injectors (excessive flow); Excessive fuel pressure due to a defective regulator; Dirty air sensor or blocked air filter.

Can I drive with fault code P0172?+