Now that the summer months have been coming I have noticed that my 87 subaru GL hatch has been almost always heating up to a hair below the red mark on the temp gauge. The strange thing is it doesn't ever blow its cap compared to my other wagon which would if it even got near 3/4 to red. It has plenty of coolant and I have the fan wired up to the ignition so its getting plenty of cooling to it. You think its possible the temp gauge is just inaccurate?

Bad cap

Bad Thermostat

Clogged Radiator

Decrepid radiator.

Alt weirdness.

 

Not good to let this be, need deeper investigation.

Temp gun? Shop gauge? Thermo-couple for your DMM?

 

Lots of ways to check this.

 

Asking us isn't the answer. My crystal ball has been broken since late last year.....

 

GD

At highway speeds, a spinning fan will actually DECREASE the amount of cooling air forced through the rad. If you are doing a lot of highway driving, I can see a constant fan causing overheating.

 

Of course, a temp sender is pretty cheap if you want to replace the one in your car already....