Is the 2 oxygen sensor on a 2005 Ford F-150 located passenger or drivers side of engine?

On a 2005 Ford F-150, the location of the second oxygen sensor (O2 sensor) depends on the engine configuration (4.2L, 4.6L, 5.4L). There's no single answer.

To find it, you'll need to:

1. Consult your vehicle's repair manual: This is the most reliable method. The manual will have diagrams showing the exact location of all sensors.

2. Use a repair database: Online repair databases (like AllDataDIY, Mitchell 1, etc., often requiring a subscription) will show sensor locations based on your VIN.

3. Visually inspect the exhaust system: The second O2 sensor is typically downstream of the catalytic converter. Be careful when doing this, as the exhaust system gets very hot.

Without knowing the specific engine, it's impossible to say definitively whether it's on the driver's or passenger's side.