I recently replaced the radiator on my aging WRX due to the top part of the rad busting at the seam and spraying coolant like a fountain. That was about a month ago.
Well now that the weather is getting colder i had to turn on the heat today for the first time since i bought the car (well besides testing to see if the heat worked after the rad install which it did. both ac and heat work great).
After a few min of going down the road i notice my temps are SOARING. The needle almost got to the red line. I immediately killed the heat.and the temps went back down slightly. We made sure to refill and burp the cooling system completely when we changed the radiator but we never replaced the thermostat.
Could this be the reason why its doing this? I topped off the coolant in the reservoir and also the cap up on the block itself. Making sure to squeeze the upper hose a few times to remove any bubbles in system.
If indeed the thermo needs to be replaced is this a valid item to purchase as a replacement? Im not looking for a race ready component. This subie is strictly a daily beater I do like to take care of it tho.
She has 163k now ^_^
Beck Arnley Thermostat