1993 Pontiac Sunbird Owner's Manual - Page 166

1. When the engine is cool, remove the Adding Coolant ( 2 . 0 ~ ENGINE) ~4 To Check Coolant When your engine is cold, coolant the level should beat FULL COLD or a little higher. When your engine is warm, the level should be FULL COLD or at higher. Your enginealso has a thermostat housing with a pressure cap. This cap and the thermostat must be taken out to add coolant. To Add Coolant If you need morecoolant, add the proper mix at the thermostat housing, but only when the engine is cool. thermostat housing pressure cap and the thermostat. Without pressing down on the pressure cap, turn itslowly to the left until it reaches a "stop." If you hear a hiss,it means there is still some pressure. Wait for hiss the to stop. Then press down on the pressure cap and continue turning it to theleft. Remove the pressure cap. Take the thermostat out of the housing. 2. Add the coolant mix to the thermostat housing until the level reaches the thermostat housing pressure cap seat. 3 Put in the thermostat. Be sure it is . fully seated. 4. Put on the thermostat housing pressure cap. Whenit's tight, the arrows on the cap should line upwith theradiator inlet hose on the thermostathousing. 16E I . .