Okay, so since I bought my car I've known of several important issues that needing fixing. The clutch, leaking top radiator hose, and drive belts that are getting old. The clutch has been replaced, and yesterday I replaced the top and bottom radiator hoses. This was quite the project (for me), and along with the exhaust change, the first work i've done on my wrx.
So I drained the radiator system and removed both of the hoses, and replaced them making sure there weren't any kinks and the clamps were secured tightly. I then mixed some subaru coolant as a 50/50 mix with some distilled water and topped off the radiator system. Put everything back in it's place and started the car. As the handbook says, let it idle for about 5 minutes around 2 to 3k rpm. Took it out for a short 5 minute drive, then came back parked it and everything seemed fine.
Drove it to work this morning, and about 5 miles into the drive I noticed the temperature guage had spiked and was maxed out on red. This was alarming, cause of the work I had done on the car the night before! gah. So I pulled over immediately and checked the oil and carefully felt the radiator. The oil was at it's normal level and nothing in the engine bay was unusually hot to the touch. At this point I was about to be late for work, so because the engine didn't seem to actually be overheating , I just limped the next 5 miles to work keeping my eye on the temp guage, which was just below max the whole way there. I checked the engine again once at work, and despite the frightfully high guage, everything seemed normal under the hood I did notice the coolant in the resevoir drop around 2 inches, from above the full line, to right at it. Im thinking there might have been some air in the engine causing the overheating, and that's where the extra coolant disappeared to? None of the hoses were leaking and both radiator caps were not extremely hot. I took one off after about 5 minutes, and some air came whooshing out.
I feel like the system just needs to get balanced, so I let the engine idle for a few minutes with one of the caps off, then eventually put it back on, I sat in the car and slowly revved it to about 4k a few times, and everytime I did the temp guage climbed almost as fast as the engine rpms did. This is the part that is really confusing to me, is the gauge misreading, or is some kink in the system causing this? Any thoughts at all would be helpful! Thanks