My truck was due an inspection. Check Engine light illuminated on the way to inspection site! Dangit!
I pulled the codes - P2196 and P2198.
P2196: 02 A/F Sensor Signal Biased/Stuck Rich (Bank 1 Sensor 1)
P2198: O2 A/F Sensor Signal Biased/Stuck Rich (Bank 2 Sensor 1)
Potential causes of a P2198 code include:
Oxygen (O2) or A/F ratio sensor or sensor heater malfunction
Open or short in O2 sensor circuit (wiring, harness)
Fuel pressure or fuel injector problem
Faulty PCM Intake air or engine vacuum leaks
Faulty fuel injector(s)
Fuel pressure too high or too low
PCV system leak/fault A/F sensor relay faulty
MAF sensor malfunction
ECT sensor malfunction
Air intake restriction
Fuel pressure too high
Fuel pressure sensor malfunction
Fuel pressure regulator malfunction
Note on some vehicles that have been modified this code may be caused by the modifications (e.g. aftermarket exhaust, headers, etc.).
Fudge. Began reading what others had found. Checked a few forums, etc. One forum thread suggested cleaning the MAF sensor and replacing the filter. My filter was only in the 10-15K mile range, but what heck. New filter, CRC MAF cleaner (under $20 bucks). Cleaned MAF sensor, let it dry. Replaced filter. Drove 10-12 miles - boom! CEL went off, passed emission test with flying colors (which is tough, as I am color blind).
KJ
I pulled the codes - P2196 and P2198.
P2196: 02 A/F Sensor Signal Biased/Stuck Rich (Bank 1 Sensor 1)
P2198: O2 A/F Sensor Signal Biased/Stuck Rich (Bank 2 Sensor 1)
Potential causes of a P2198 code include:
Oxygen (O2) or A/F ratio sensor or sensor heater malfunction
Open or short in O2 sensor circuit (wiring, harness)
Fuel pressure or fuel injector problem
Faulty PCM Intake air or engine vacuum leaks
Faulty fuel injector(s)
Fuel pressure too high or too low
PCV system leak/fault A/F sensor relay faulty
MAF sensor malfunction
ECT sensor malfunction
Air intake restriction
Fuel pressure too high
Fuel pressure sensor malfunction
Fuel pressure regulator malfunction
Note on some vehicles that have been modified this code may be caused by the modifications (e.g. aftermarket exhaust, headers, etc.).
Fudge. Began reading what others had found. Checked a few forums, etc. One forum thread suggested cleaning the MAF sensor and replacing the filter. My filter was only in the 10-15K mile range, but what heck. New filter, CRC MAF cleaner (under $20 bucks). Cleaned MAF sensor, let it dry. Replaced filter. Drove 10-12 miles - boom! CEL went off, passed emission test with flying colors (which is tough, as I am color blind).
KJ