2006 Pontiac Solstice Owner's Manual - Page 214
2006 Pontiac Solstice Manual
Page 214 highlights
Adding Coolant {CAUTION: Turning the surge tank pressure cap when the engine and radiator are hot can allow steam and scalding liquids to blow out and burn you badly. Never turn the surge tank pressure cap - even a little - when the engine and radiator are hot. The vehicle must be on a level surface. When your engine is cold, the coolant level should be at the COLD FILL line. Do not overfill the surge tank. Too much coolant can result in an overflow condition when the fluid is hot. If you need more coolant, add the proper DEX-COOL® coolant mixture at the coolant surge tank, but only when the engine is cool. If the coolant surge tank is empty, a special fill procedure is necessary. See Engine Overheating on page 5-23 for instructions on "How to Add Coolant to the Coolant Surge Tank." {CAUTION: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol, and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine. When replacing the pressure cap, make sure it is hand-tight and fully seated. 5-22