Which trouble codes do owners report?

P0172 System Too Rich is the largest group at 32, out of 2,214 complaints.

P0172 System Too Rich32

P0430 Catalyst System Efficiency Below Threshold24

P0304 Cylinder 4 Misfire Detected22

P0303 Cylinder 3 Misfire Detected16

P0301 Cylinder 1 Misfire Detected15

P0300 Random/Multiple Cylinder Misfire Detected14

P0302 Cylinder 2 Misfire Detected14

P0420 Catalyst System Efficiency Below Threshold12

The code owners quote most is P0172. Read your own code from a scan and give the shop the exact code, not only "the light is on".

Source: NHTSA owner complaint files · downloaded 2026-10-05