All of a sudden my car has been beeping really loudly inside the cabin and showing the low coolant light but when i go to check the coolant level its fine. Car has run absolutely flawlessly since i bought it so this is rather troubling. And yesterday it started to run much hotter than normal, like 3/4 of the way up the temperature gauge vs the normal 1/2 or so. Maybe i need a new radiator cap? Any ideas as to what it could be?

 

Also the coolant has been just bubbling like crazy after i turn the car off, didnt do that before.

Think my water seals could be shot?

 

BUT, the coolant light and sound STOPS while im driving and doesnt typically happen after ive driven it even a little bit.

 

Where are you checking it? At the overflow or the radiator? Since your profile says 90 vert you can check the level in the Rad.

This worries me as the S5 gauge doesn't tend to move until it is already too hot. Could be low and when your driving there is enough flow over the sensor to keep it happy.

 

At the overflow is where i was checking

 

With it cold/cooled down enough that there isn't pressure in the system so you don't get sprayed with hot coolant check it at the radiator.

Also I have seen bad radiator caps that would let the system push coolant out to the overflow but would never draw it back into the radiator as it cooled as it should. After multiple times of this you don't have enough coolant in the system anymore and overheating occurs.

 

When i mentioned it to my dad his first thought was the radiator cap but thats best case scenario here

 

The radiator cap is not directly on top of the rad itself as im sure you know so theres just a pipe up to the top of the bay where the cap is, should the level be visible through the cap?

 

Yep. When I had the stock radiator I always filled/kept it where fluid was visiable in that tube just below the cap. I'd replace the cap as they don't cost much while I was at it.

 

Alrighty then. I will keep updating as i find things out

 

Let the car sit overnight and apparently the car actually was very low on coolant. Whoops. Anyway it runs great still and is not overheating or running ridiculously hot anymore.
But my question is that could i be losing coolant? What would it mean if i am?

 

You could be losing coolant in different ways. Could be an external leak or an internal leak. An internal leak would likely be caused by a coolant seal failure and the coolant is mixing in w/the fuel and being burned off.

 

mine did that because the overflow reservoir was low. also make sure you have no bubbles in the system

 

Theres absolutely no smoke from the exhaust though so i feel like thats out

 

Gonna burp the system the day after tomorrow

 

any luck?

 

There doesn't need to be smoke coming from exhaust. Just had this same issue with my engine, 87' TII, and it didn't smoke until the very last day it was able to run. This was only because it failed completely. Only had 60K on the original motor, though I believe when it was sitting for almost two decades that it had coolant in it at some point, possibly eating away at the iron. I'll know more about mine in a couple weeks when Banzai starts the rebuild. Your issue sounds almost identical.

Has any steam come out of the radiator cap opening when you had the cap off?

 

Nope

 

Wasnt able to find the time this weekend.