Where is the O2 sensor for bank one located on a 1998 Oldsmobile Intrigue GL?
Generally, if bank one O2 sensor has failed, bank 2 will fail soon, assuming it’s either a V6 or V8. Inline engines only have the front O2 sensors. It’s a good idea to do both at the same time if it’s V configuration engine. They are on the exhaust manifold, right before the connection to the headpipe. It will be the only thing connected to the exhaust that has wires.