Quick question on banks and O2 sensors when it comes to error codes: P0420 - Catalyst System Efficiency Below Threshold (BANK 1) P0430 - Catalyst System Efficiency Below Threshold (BANK 2) P2198 - O2 Sensor Signal Stuck Rich BANK 2 (SENSOR 1) May I know, where is the system referring to for BANK 1 and BANK 2 ? And Sensor 1 and Sensor 2 ? I have an image below illustrating the 2 O2 sensors (Green & Blue) on one side of the F430 engine: Image Unavailable, Please Login Bank 1 refers to the RIGHT side of the engine and Bank 2 refers to the LEFT side of the engine ? Sensor 1 refers to the PRECAT 02 Sensor (at the headers) and Sensor 2 refers to the POSTCAT 02 Sensor ? I have an aftermarket high flow cat I know, but shouldnt this only trigger Sensor 2 and not 1, since Sensor 1 means PRECAT (at the headers) ?
Precat means before the primary cat and doesn’t refer to the precats in the headers. I know - a bit confusing. Sensor 1, the precat sensor, measures the air/fuel ratio coming out the header and before the main cats. It’s readings determine any adjustments made by the ecu to the fuel mix. The postcat sensor means after the main cat. It’s readings are compared to the precat readings to see how well the main cat is working. I would start by replacing the precat sensors (sensor 1) on both banks They are easier to replace and you should do them together. They are also the ones that typically fail first, and incorrect readings from them can cause the comparison with the reading from sensor 2 to be outside the threshold. The sensor 2s are most likely fine although while you are there no harm in unscrewing them and cleaning with vinegar and a toothbrush. Sent from my iPhone using Tapatalk
