The most likely common denominator for the temp and fuel gauges is a common ground. Does the truck have any aftermarket or dealer installed accessories like a remote start, audio system, GPS, etc.?
It's a 2002 Tacoma. Check for rust...
No aftermarket anything, Ray. Only two things have happened to the truck in recent weeks: I changed the light bulbs for the ash tray and glove box. While doing this, I discovered that Toyota is using former "engineers" from General Motors, because there was barely enough slack to allow me to handle the bulb socket correctly. It required a bit of tugging. I wonder if something was dislodged.
I also installed the rubber winter footmats. Uh oh. Another footmat disaster....
Toyota used a fair number of GM suppliers for vehicles assembled at the NUMMI plant.
I don't think that changing bulbs or tugging on a bulb socket for the ash tray or glove box would cause the problem,
Unscrew the screws on the underside of the bezel surrounding the instrument cluster and tilt the cluster forward to see if you can see any loose wires.
Bad ground. OR, you're out of gas and the motor is cold.
I noticed that you told Ray that you had to tug on some wires to get the light sockets to come out far enough to change the lamps. I'm gonna second Ray's suggestion to pull the instrument cluster out and see if you unplugged something. You probably unplugged something while yanking the wires around. I don't recall the layout of the guages in my daughter's Tacoma, but if they are adjacent to one another, I'd expect you to have pulled the connector off.
They use a lot of ribbon cables that are easy to unplug. They might be easier to unplug than to plug in again. You should be prepared to not find wires, per se, connecting the guages.
From left to right, the arrangement is temp gauge, tach, speedo, fuel gauge. But it's probably still just one bundle for the two that are having a problem.
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