Generally, however, the knock sensor is located on the engine block, usually near the cylinder head, often on the passenger side (right side when looking at the engine from the front). It's a small, threaded sensor.
To find it with certainty:
1. Find your engine size: Check your vehicle's paperwork or the sticker on the driver's side doorjamb.
2. Use a repair manual: A Haynes, Chilton, or factory service manual for your specific year, make, model, and engine will show you the exact location with diagrams and photos. This is the most reliable method.
3. Use an online repair database: Websites like AllDataDIY or Mitchell 1 (subscription required) offer detailed repair information, including sensor locations, with diagrams.
4. Search online for images: Try a search like "2003 Chevy Avalanche [your engine size] knock sensor location" – you might find helpful images from forums or repair websites.
Caution: Before attempting any work yourself, disconnect the negative battery terminal. Be careful not to damage the sensor or surrounding components during your search or replacement.
