Where is the oil pressure sending unit on a 4.3L engine?

The location of the oil pressure sending unit on a 4.3L engine varies slightly depending on the year and specific make of the vehicle (GM, etc.). However, it's generally found on the driver's side (left side) of the engine block, near the oil filter. It's often a small, threaded sensor with one or two wires connected to it.

To be certain, you should:

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

2. Look at online diagrams: Search for "[Your Vehicle Year, Make, and Model] 4.3L engine diagram" on the internet. Many sites offer free diagrams, but double-check the accuracy against the year and model.

3. Visually inspect the engine: Once you have an idea of the general location, carefully look around the oil filter and lower portion of the engine block on the driver's side. The sending unit is usually fairly easy to spot.

Caution: Always allow the engine to cool completely before working on it. Oil under pressure is hot and dangerous.