There are actually 4 O2 sensors on your truck. IF you look inside the wheel wells behind the fender liner, right about where the frame is one O2 sensor, the other is underneath the truck about half way back in relation to the transmission. IF you see where the exhaust joints together, you went about 6" too far.
When you start looking at the O2 sensors, they are normally numbered something like "Bank 1 Sensor 1" Bank 1 is on the passenger side; Bank 2 is on the driver's side. Sensor 1 is the upstream sensor (near the frame, between the block and the cat) and Sensor 2 is near the Y-pipe (downstream of the cat).
Normally it is the upstream sensors (sensor 1) that go first. They see the harshest conditions.
On a 1998 Ford F-150 or Ford Expedition , 5.4 Bank 2 is the drivers side of the engine Sensor 1 would be close to the engine BEFORE the exhaust enters the catalytic converter
Bank 2 is the drivers side of the engine in a Ford Expedition
Bank 1 is the passenger side of the engine in a Ford Expedition
Where are the Bank 1 Sensor 1 oxygen sensor on a 1998 ford explorer?
On a 1998 Ford Expedition : Bank 1 is the passenger side of the engine ( 4.6 and 5.4 ) Sensor 1 would be close to the engine BEFORE the exhaust enters the catalytic converter Sensor 2 would be AFTER the exhaust has passed through the catalytic converter ( also called a catalyst monitor )
where is speed sensor location 98 ford expedition 4.6 engine nocruise control
Bank 2 is the drivers side of the engine in a Ford Expedition Sensor 2 is after the catalytic converter ( downstream )
Bank 2 is the drivers side of the engine in your Ford Expedition Sensor 1 is in the exhaust BEFORE it enters the catalytic converter ( upstream )
Bank # 1 is the passenger side of the engine in a Ford Expedition Sensor # 1 would be before the catalytic converter ( upstream sensor ) Sensor # 2 would be after the catalytic converter ( downstream sensor )
Bank 1 is the passenger side of the engine in your Ford Expedition Sensor 1 is in the exhaust before it enters the catalytic converter ( upstream )
In a Ford Expedition bank 1 is the passenger side of the engine , bank 2 is the drivers side
Bank 1 is the passenger side of the engine in your Ford Expedition Sensor 1 is in the exhaust system before the exhaust enters the catalytic converter ( upstream )