Why does the temperature gauge goes up and down. Heater blows cold air when it's up and hot (warm) air when it goes down.
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1997 GMC Jimmy Question: Heater problems
Answer #1dandd January 08, 2010, 11:09Master
You could have a sticking thermostat that sticks and then the engine and gauge gets too hot, then it opens and the coolant flows but it flows too much and the heater and gauge gets too cold.
Answer #2Bret Bodas from RepairPal Test Shop, January 08, 2010, 11:15Master
Check the coolant, make sure you don't have a problem, see this for more info: http://www.consumeraffairs.com/automotive/gm_dexcool.html