F430 CEL with P2198 (O2 Sensor Signal Biased/Stuck Rich Bank 2 Sensor 1)

Today I got a CEL when driving my F430. The car seemed to be driving fine. The light is solid, not blinking. I pulled the codes and there is just one active and one pending, and both are the same code: P2198. Some help from Google shows this as "O2 Sensor Signal Biased/Stuck Rich Bank 2 Sensor 1".

I'm not very technical when it comes to DIY on my cars, but before I take it to the dealer I'm wondering if others have encountered this before. I found one reference to a P2196, which is the same error but on Bank 1. That thread did not have a resolution posted.

Any ideas on what may cause this?

TIA
-Mike

 

So based on the lack of replies I assumed nobody is familiar with this and went to the dealer. It turns out this was my own fault. Apparently when I'm gassing up I'm over filling the tank. I noticed shortly after getting the car that when the gas pump clicks off, if I restart it just once it takes another gallon. So that was my typical MO.

The explanation I got was that I was over filling the tank and putting gas into some ventilation tubes. That ends up splashing into some charcoal packets. And somehow the evaporating gas ended up getting sucked into an air intake. This caused a rich condition that was detected by the O2 sensors and triggered my CEL.

Dealer flushed out the tubes and charcoal packets and cleared the code and all seems back to normal. I just fill up slightly more often now

 

Here is an article that describes the general usage of activated charcoal to capture fuel vapor, and why topping off causes issues.

Don't be a moron: Stop topping-off your gas tank.