JCGMS

2006 997 C2 3.6 100K miles. Gundo Hack 5 years ago.

P2198 O2 Sensor Signal Biased/Stuck Rich (Bank 2 Sensor 1) Code popped up recently and won't clear.

I swapped the blue wired sensors (pre Cat, closer to outside of car rather than center) from side to side and am still getting the same error code despite trying to clear repeatedly.

On my iphone OBD2 reader the short term fuel % trim on Bank 2 doesn't fluctuate.

Any suggestions on further steps to troubleshoot prior to giving in and taking to mechanic?

Thanks.

JCGMS

To answer my own question: CEL would clear with OBD2 reader but re-appear every time I restarted the engine, even after installing new sensors (at 100K I figured it was time for new ones regardless). The solution was to disconnect the battery for a few minutes to clear the ECU, CEL now gone (fingers crossed it stays that way).

Tper8181

Did this solve the problem ? My p2198 seems to return after clearing the code

JCGMS

Correct, no more codes in the 2 years since I wrote the post. To repeat, I still got the code even after replacing the sensors and re-clearing with OBD. It didn't go away fully until I disconnected the battery to reset the ECU.

Tper8181

I can’t seem to get rid of mine
changed the AOS
new o2 sensors all round
changed the purge valve under the inlet manifold
new oil cap
new fuel cap
new fuel pump
new coil packs

only mods on the car are sprint booster and miltek cat back

doing my head in

JCGMS

Tper, I know it sounds silly but did you reset the ECU by disconnecting the battery for a length of time ('til you get the PSM warning on startup)? That's what eventually cleared my code.

Tper8181

I did
i actually had the firewall positive terminal so the car was completely reset back to factory settings

It’s very frustrating I thought somebody would of had the easy fix