Where is the crank sensor in a 1991 Chevy 5.7l v8?

On a 1991 Chevy 5.7L V8 (likely a TBI or early TPI system), the crankshaft position sensor (CKP sensor) is typically located on the passenger side of the engine block, near the front of the engine, and usually pointed towards the crankshaft pulley. It's often mounted in a bracket or directly to the block.

However, the exact location can vary slightly depending on the specific engine and transmission configuration. It's best to consult a repair manual specific to your 1991 Chevy 5.7L V8 model (the VIN can help identify the exact engine code) for a definitive answer and diagrams. A visual inspection with the engine bay cleaned up will also be very helpful.