To find it, you need to determine:
1. Engine: Is it a 5.7L or a 7.4L? The engine size influences the exact location.
2. Upstream or Downstream: Are you looking for the pre-cat or post-cat sensor? The upstream sensor is closer to the engine.
3. Driver's side or passenger's side: Bank 1 is typically the driver's side, therefore Bank 2 is the passenger's side. On your 1999 Suburban, Bank 2 is the passenger side.
Once you know that information:
* Consult a repair manual: A Haynes or Chilton repair manual specific to your 1999 Chevy Suburban (and its engine size) will have diagrams showing the exact location of both Bank 2 O2 sensors (pre and post-cat). This is the most reliable method.
* Use a parts diagram: Many auto parts websites (like AutoZone, Advance Auto Parts, etc.) allow you to select your vehicle's year, make, model, and engine, then view diagrams showing sensor locations.
General Guidance (but not guaranteed to be precise for your specific vehicle):
The sensors are usually located in the exhaust manifold or in the exhaust pipe near the catalytic converter(s). You'll likely find them screwed into the exhaust components. They're typically wire-connected.
Without knowing the engine size and whether it's pre-cat or post-cat, I can't give you a more specific location. Using a repair manual or online parts diagram is absolutely necessary for accurate identification.
