So a few weeks ago my truck did this weird thing where at a red light in Columbia i look down and its way hotter than normal so I switch to heat in the cab to get some hot air off the motor cause my dad always preached that when I was little and it almost immediately goes back to normal running temperature so I turn the ac back on and it's fine till I get home. Few days later same thing. Take the thermostat out its clean and not stuck at all drain all the coolant and run water through till it comes out clean and then fill it up and get the bubbles out of the system. So I pulled in tonight with the gauge reading normal operating temperature and rev the truck to 1200 Rpms and it blows water out of the overflow cap any idea why the gauge is going crazy? Also there was a wire or something melted in the engine bay. Pictured somewhere in this post can't tell on my phone

 

The residue on the overflow bottle looks cruddy and even a little rusty. With a 14 year old truck, I'd change out the water pump and thermostat if they haven't been done already.

 

Changed the tstat when I did the intake manifold 6 months ago but if I take it all apart I'll replace it when I get the cooling system apart

 

I am guessing that you bought the truck used not long ago like shortly before you did the intake manifold. I suspect the previous owner had cooling system problems and he most likely over heated the engine at some point. I would do a check of the cooling system to see if you are getting exhaust gas in the coolant which would suggest that you have a blown head gasket. As far as the fix to this, in a word "expensive". That crud looks like some type of sealer to stop a leak or a blown head gasket. So in summary, I would first decide if it is worth fixing a blown head gasket on your truck. You might just want to see if it is not so bad and if you can just live with it before you spend money on a test to see if you have a blown head gasket (i.e. a repair you might not want to perform).

 

I've had the truck 4 years and 40,000 miles it runs great and hasn't had any cooling issues up until 2 weeks ago and it's hot here in Columbia South Carolina. I don't think There's any way it's getting as hot as the gauge says it is as fast as the gauge climbs and falls. It will go from operating temp to almost all the way to the H in a matter of seconds and drop back down to operating temperature in just a few seconds also

 

I agree with Frank, that looks like some Bars Leaks - Head Gasket Fix was put in it. It works pretty decent on small leaks, but it makes a mess.