1998 Pontiac Firebird Owner's Manual - Page 282

NOTICE: If you use an improper coolant mixture, your engine could overheat and badly damaged. be The repaircost wouldn't be coveredby your warranty. Too much waterin the mixture can freeze and crack the engine, radiator, heater core and other parts. If you have toadd coolant more than four times a year, have your dealer check your cooling system. Checking Coolant I NOTICE: If you use the propercoolant, you don't have to add extra inhibitors additives which claim to or improve thesystem. These can be harmful. When yourengine is cold, check the dipstick on the cap of the coolant recovery tank. The coolant level should be at COLD, or a little higher. When your engine is warm, the level on the dipstick should up to HOT, or be a little higher. 6-29