2001 Buick Regal Owner's Manual - Page 280

Checking Coolant The engine coolant recovery tank is located on the passenger's side of the vehicle at the back of the engine compartment. See "Engine Compartment Overview" in the Index for more information on location. The vehicle must be on a level surface. When your engine is cold, the coolant level should be at the COLD mark or a little higher. When your engine is warm, the level should be up to the HOT mark or a little higher. If this LOW COOLANT light comes on and stays on, it means you're low on engine coolant. If you need more coolant, add the proper DEX-COOLR coolant mixture at the coolant recovery tank, but be careful not to spill it. If the coolant recovery tank is completely empty, add coolant to the radiator. See "Engine Overheating" in the Index. Adding Coolant 6-29