1998 Buick Regal Owner's Manual - Page 291

Radiator Pressure Cap NOTICE: Your radiator capis a 15 psi (105 kPa) pressure-type cap and must be tightly installed to prevent coolant loss and possible engine damage from overheating. Be sure the arrows on the cap line up with the overflow tube on the radiator filler neck. When you replace your radiator pressure cap, an AC@ cap is recommended. Power Steering Fluid Thermostat Engine coolant temperature is controlled by a thermostat in the engine coolant system. The thermostat stops the flow of coolant through the radiator until the coolant reaches a preset temperature. When you replace your thermostat, an AC@thermostat is recommended. When to Check Power SteeringFluid It isnot necessary to regularly check power steering fluid unless you suspect there is a leak in the system or you hear an unusual noise. A fluid loss in this system could indicate a problem. Have the system inspected and repaired. 6-27