What is the Locationof oil pressure sending unit 1999 5.7l Chevy motor?

The location of the oil pressure sending unit on a 1999 5.7L Chevy engine (likely a Vortec) varies slightly depending on the specific engine configuration and whether it's a truck, SUV, or car application. However, it's almost always located on the driver's side (left side) of the engine block, near the front.

To be certain:

1. Consult your owner's manual: This is the best resource for the exact location on your specific vehicle.

2. Look for a small, typically one-wire sensor: It's a relatively small cylindrical device screwed into the engine block. It's often near the oil filter, but not always directly next to it.

3. Use a repair manual or online diagrams: A repair manual specific to your year and model Chevy will have diagrams showing the exact location of all sensors. Online resources like AutoZone, Advance Auto Parts, or Haynes/Chilton manuals often have these diagrams. Search for "1999 Chevy 5.7L engine diagram" to find such a resource.

Be careful when working around the engine; it's hot when recently run, and oil is under pressure. Allow the engine to cool completely before working on it.