1997 Buick Regal Owner's Manual - Page 258

2. Then keep turning the pressure cap, but now push down as you turn it. Remove the pressure cap. l... 3. After the engine cools, open the coolant air bleed valve. .. .. 'I /$\ CAUTION: I I There is one bleed valve. It is located on the thermostat housing. I You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and itwill burn if the engine parts are hot a enough. Don't spill coolant on hot engine. 5-22