What P0172 means
System too Rich (Bank 1)
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P0172:
| BMW | System Too Rich |
| FIAT | Air / Fuel Ratio (level 1) |
| FORD | System Too Rich (Bank 1) |
| HONDA | Fuel System Too Rich |
| MITSUBISHI | System Too Rich (Bank 1); Fuel trim СЏtoo rich |
| NISSAN | System Too Rich (Bank 1) |
| VOLKSWAGEN | Fuel Trim System Rich Bank 1 |
Read this code on your own car
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