2004 chevy avalanche overheating

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Right, plates of full depth and weight ... Loose hold-downs - bouncing arounddamages a battery several ways ... Excessive loads - using the starter to move thecar should be only a ... ask for a temperature-corrected hydrometer reading, which should be 1.260 specific gravity. ... All this is dependent on the individual car.

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temp gauge bouncing around before going to center? ' Yahoo Answershttps://answers.yahoo.com/question/index?qid...Sep 28, 2013 - I called my mom and we switched cars and she didn't see anything ... Best Answer: If the temp gauge is literally "bouncing around" this is more ...Why is my temperature gauge jumping?Jan 1, 2013Temperature gauge bouncing.?Dec 18, 2008What does it mean, when my coolant temp needle jumps up and ...Oct 3, 2008My car temperature gauge keeps bouncing around from cool to red ...Dec 12, 2006More results from answers.yahoo.comTemperature Gauge Jumping Around an

So did you check the gauge and the sending unit ?
Either component could be faulty.

I would suspect the thermostat first.

Defective hose?

replace the thermostat,, and make sure that the fan engages , just because the fluids don't boil over doesn't mean the temp isn't to high, if your saying that the temp gauge is stuck on the hot setting, and doesn't move even when the car is cold,, thats a different problem,, if thats the case whats the make , model , and year

I don't think it's the thermostat, so much, as the circuit for the temperature gauge which includes, wiring to the cts (coolant temperature sender), the cts itself, and the gauge. It's likely a wiring problem if it randomly bounces from normal to hot while driving the vehicle or standing still.

First of all you have a bad heater core that needs to be replaced. Second you may have a bad temperature sensor. Make sure the radiator if full of water

this problem is caused in almost all cases by a failed actuator that moves the door insiode the heating/ac duct to change the outlet temperature, it is called the Air Temperature Control Blend Door actuator.

it is most likey a sticking thermostat it either gets stuck closed or open in your case closed so collant isnt getting to the heater core and all you get is cold air blowing into the truck.
its a simple fix you can either do it your self or take it to a mechanic. now remember there are differnt thermostes so think about the climat you live in and get one according to that

It may be the thermostat