jpark

I was driving home last night and it was cold so i had my heater on like usual. However, noticed that the cabin wasn't getting warm and it was actually blowing cold air.
i also immediately noticed that my temperature guage was reading 4 bars instead of the normal 3 (ap1)

i turned the heat off completely, and continued driving with my fingers crossed and the temp guage bar went back down to the normal 3, and my heater and everything started working completely fine again..

any ideas?

emdzey01

Check your coolant level; there has to be a leak somewhere... Find out if theres still coolant in the reservoir.

Did you do a coolant flush lately? The system might have needed to "burp" if so.

ndogg

Sounds like you have air in your coolant system. Bleed the air out using Billmans method.

https://www.s2ki.com/s2000/topic/818...h/page__st__25

S~Factor

I found that the car has to be on a level ground or the front higher than the rear for it to release air in the system (burp). I had the rear raised up and it would not finish releasing air.