Where are the spark plugs located on a 1991 Toyota Camry?

The spark plugs on a 1991 Toyota Camry are located on the top of the engine, under the valve cover. To access them, you'll need to remove the valve cover. There's one spark plug per cylinder, and the Camry typically has a 4-cylinder engine (although some models had a V6). Therefore, you'll find four spark plugs arranged in a row across the top of the engine. You'll need a spark plug socket and possibly a ratchet to remove and replace them. Consult a repair manual specific to your 1991 Camry engine (either 4-cylinder or V6) for precise location diagrams and removal instructions.