Where is the oxygen sensor located on a 86 Chevy S10 2.8 engine?

The oxygen sensor (O2 sensor) location on a 1986 Chevy S10 with a 2.8L V6 engine is typically in the exhaust manifold, near the engine's exhaust port. There's usually only one O2 sensor on these older models.

However, to be absolutely certain, you should:

* Consult your owner's manual: This is the best resource for precise location information specific to your vehicle.

* Look at a repair manual specific to your year and engine: Repair manuals (like Haynes or Chilton) have detailed diagrams showing the sensor's location.

* Visually inspect the exhaust manifold: The sensor is usually a threaded cylindrical device with a single wire leading to it. It's usually near one of the exhaust ports.

Keep in mind that the exact placement can vary slightly depending on the specific configuration of your exhaust system. Be cautious when examining the hot exhaust system; allow it to cool completely before working near it.