Your best bet is to:
1. Consult your owner's manual: This is the most reliable source. The manual should have a diagram showing the location of all relays and fuses.
2. Check the fuse box diagrams: There are usually diagrams on the inside of the fuse box covers (both under the hood and inside the car, if there's one). Look for a legend that identifies the fuel pump relay.
3. Use a wiring diagram: A detailed wiring diagram for your specific year, make, and model LeSabre will pinpoint the relay's location. You can find these online (often for a fee) through automotive repair sites.
4. Search online forums: Search forums specific to Buick LeSabres (like on sites like car forums or repair specific sites) and search for "fuel pump relay location 1996 Buick LeSabre." Someone may have already asked and answered this question with a picture.
Without knowing the specifics of *your* 1996 Buick LeSabre, it's impossible to give a definitive answer. The above steps are the most reliable ways to find it.
