in chasing cooling problems, come back to the basics.
its the engines job to heat up the coolant and dump it back into the radiator at ANY temp over the t-stat (160,180,195). the temp gauge measures this temp and displays it on the dash. if your temp sensor is working, then its fairly accurate.

its the radiators jobs to lower the temp from real hot (195 ish) at the upper pipe to real warm (150 ish) at the lower pipe. you can measure this with a sophisticated heat gun, or your hand. 195 is too hot to hold. 150 is tolerable to your hand. if the radiator is not dropping your coolant temp by 50 degrees or more, there's something wrong with your rad. a simple check here is to clean the radiator's air flow by spaying water or air backwards through it. the radiator air path can get stopped up with mud or grass seeds (been driving across the hay field?)

its the fan's job to spin with slight resistance, and not free wheel when you turn off the engine. its the water pump's job to move coolant and not leak. its your job to keep the system full of 50/50 or so mix.

common major malfunctions.
leaking head gasket or cracked head puts air pressure in the block, causing air lock, no coolant flow, and overheating.
bad t-stat opening too soon, or too late or bad flow - broken parts or stopped up including old pieces of gaskets, old t-stat parts, freeze plugs, or any other foreign objects.
stopped up radiator core. mineral deposits, sludge, etc stopped up air path - mud, grass.

test the radiator by checking hose temps at top and bottom.
test the whole system by removing the t-stat completely. if it won't cool with no t-stat. then the whole thing is exposed for you, and the t-stat is eliminated as a cause.

 

If the water pump is gushing water and the thermostat opens, then you're wasting time and money replacing either or both.

Flush the block, flush the radiator, refill with coolant, and possible pressure test your setup. I know that Autozone rents a gauge that attaches to the radiator to test if your system holds pressure.


After all that and it's still running hot, get the timing checked. Disregard what all the swap artists are telling you about "swap this, swap that, it's only money". I agree with you that the gauge is telling, regardless what a lot of people here say. The sign I have that mine is running hot is that it will spit coolant out of the overflow and into the engine bay. It confirms what the gauge is telling me.

 

Do you have any "dead" cold spots on the rad?

 

OK I've got NEW INFORMATION.

When the car runs hot, with the needle nearly nearly all the way up, I turned on the heat and pumped it on high. The temp dropped to between the top and middle of the gauge.

Does this mean that the radiator is bad?

 

Have you flushed your cooling system yet?

 

nope not yet, i wanna do it on Sat, and i'll also be taking out my radiator and blow compressed air through it in the opposite direction.

 

Compressed air won't do it. You need an adapter to pressure blast it with water. Sounds like you may have a blockage and/or an air pocket that hasn't burped out. Your heater core acts like a secondary radiator when the HVAC fan is set to the highest setting.

 

my parents have a pressure washer, maybe i'll go over to their house and do it.

 

Check your FLAPS and see if they have the adapter. The key is to reverse-flush, meaning the pressure has to enter the bottom (lower) radiator opening. This would also be a great opportunity to flush the block; however, based on your description of the water-pump flow, I think your block is free of any blockage.

Off the top of my head, any idea as to the condition of the core plugs? Yeah, everyone calls them freeze plugs, but the proper name is core plugs. When I rebuilt my engine, I replaced the steel plugs with brass. Assuming one is compromised, air could be leaching into the system.

 

I will use the pressure washer to reverse flush and blow out gunk from the fins.

What is FLAPS?

If the freeze plugs we're bad, then coolant would be leaking when it pressurizes. Plus, I just had my tranny replaced, so they inspected them then, i asked them to.