* Upstream Sensor (Before the Catalytic Converter): This sensor is usually located in the exhaust manifold or very close to it. It monitors the oxygen content in the exhaust gases before they reach the catalytic converter.
* Downstream Sensor (After the Catalytic Converter): This sensor monitors the efficiency of the catalytic converter. It's located further down the exhaust pipe, after the catalytic converter. Some 1997 models may not have this second sensor.
To find them precisely:
1. Consult your owner's manual: This is the best resource for the exact location on your specific truck model.
2. Check a repair manual: A Haynes or Chilton manual for your year and model will have diagrams showing the sensor locations.
3. Use an online parts diagram: Many auto parts websites (like AutoZone, Advance Auto Parts, etc.) have online diagrams you can view by entering your vehicle's year, make, and model. These diagrams often show sensor locations.
Important Note: Because there are many variations in 1997 Chevy pickup trucks (different engines, trim levels), it's crucial to use one of the above resources to pinpoint the precise location on *your* specific vehicle. Simply searching for a general location won't guarantee you find it.
