Temp guage says hot but engine seems OK

replace the engine temp sensor .. should fix your proble .. located on the block .. alot of time when they spring a leak if not shut down soon enough it can mess up the engin temp sensor

Thanks. I replaced the sensor (the last thing I did) but problem persists.

try undoing your battery for 30 sec .. sometimes the gauges can get stuck ..

I haven't tested with a voltmeter. I can do that. The guage starts normal, then goes to hot, stays there a while, then comes back to normal for a while, then hot again, etc. I've noticed that if I stop and turn the engine off when the guage is very hot, then turn it back on, the guage goes back to normal. I have also noticed smoke when accelerating after being stopped at a light.

I'll also try disconnecting the battery. Heck, I'll even dance around the truck a few times if it'll help. (jk) Thanks.

what color is the smoke that your seeing . and does it have a rough idle at all ?

The smoke looks blue-ish, although I have only looked at it through the outside mirror and the mirror may be tinting it. The idle is very smooth.

Lately, the temp guage now goes from cool to hot, from one extreme to the other, and stays at hot. If I turn the engine off and back on a few seconds later, it goes back to normal (mid range).

I appreciate your staying with me on this.