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Temperature guage

747 Views 3 Replies 4 Participants Last post by  shall36
Anyone having problems with their temperature guage? Mine started going crazy reading normal then nothing then normal. My mechanic says it's the guage not the sending unit. Cost to replace is over $500. I really don't want to run without the guage since I'm over 108,000 with all original hoses, etc. Anyone have any suggestions how I might save a few bucks?
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A fluctuating gauge could mean the thermostat is bad............nothing is another story.
With that many miles, it's a good idea to do a coolant flush, hose replacement, and you might as well change the thermostat while your at it.
You can do all of these things yourself for about $75.
Then if you still have problems go with the mechanic's recommendations.
I recommend getting haynes manual#92078 for 00-02 tundra.
The system is fairly simple: there's a sending unit, which is just a temp-sensitive resistor and there's the gauge, which is essentially a volt meter. This is an oversimplification, but you get the point. The sending unit is easy enough to check with an ohm meter. It's rare for a gauge to go bad.

The FSM has instructions on how to troubleshoot this problem.

Subscribers have access to the FSM, I think.

In any event, let's say that it IS the gauge that's bad. Do you really want to dump that kind of money into an older truck? I would encourage you to buy the ScanGaugeII and use it to "replace" your gauge. The ScanGaugueII is a small, electronic device that plugs into your trucks diagnostic port and can read out and display a number of different system parameters. I use one to monitor fuel economy AND as a temp gauge. I can't remember the cost, but it's a lot less than $500.
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