Where do you find the knock sensor in a 1999 Chevy lumina?

The knock sensor location on a 1999 Chevy Lumina depends slightly on the engine. There are two common engines for that year: the 3.1L V6 and the 3.8L V6. However, the location is generally similar for both.

You'll find the knock sensor on the engine block, near the bottom of the engine, and usually on the driver's side (left side when facing the engine). It's often located near the oil filter or on the oil pan. It's a small, threaded sensor, usually with one wire connected.

To be certain:

* Consult a repair manual specific to your 1999 Chevy Lumina's engine: A Haynes or Chilton manual will have diagrams and precise locations. This is the most reliable method.

* Use an online 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 a parts diagram showing the knock sensor's location.

Caution: Accessing the knock sensor often requires getting under the car and may involve removing some components for better access. Be mindful of hot engine components, and wear appropriate safety gear.