Bank No. 1 is on the passenger side of your 1997 Ford Expedition. The heated oxygen sensor threads into the exhaust pipe just below where the pipe mates to the exhaust manifold, and before the catalytic converter. Turn off the air suspension system before you jack up the Expedition if you need to crawl under it. When installing new HO2 sensors, tighten them to 26 to 34 foot-pounds.
Diagnostic trouble codes P1130 through P1136 are associated with the bank No. 1 HO2 sensor on your Expedition. Always note any other DTCs present since the DTC for the HO2 sensor may be the result of another problem and not the primary problem. The "Check Engine" light illuminates when the fault is detected on two consecutive drive cycles and will go out if no fault is detected on three consecutive drive cycles.
