Subaru Impreza WRZ SL AWD 2006 Coolant issue

[John C.]

Good afternoon

I have had on going coolant issues with the above vehicle to the point where the rad hoses, radiator cap, overflow cap and top coolant tank cap have all been changed. I have performed the "burp" test to try and expel any air and things seem to have improved since performing the aforementioned tasks. The issue i have now is that when sitting at idle, the temp gauge is normal, the heater is hot but the level in the overflow bottle is much higher than the high level line. Would this indicate too much water in the system as when i drive it, the temp goes up and the heater starts to blow cold and then when on idle and you dab the throttle the temp comes down on the gauge and the heater starts blowing hot again. Could there still be air in the system? Please could someone give me a glimmer of hope as its starting to drive me nuts!!!!

Cheers

JOhn

[Linx]

It's normal for the level in the expansion tank to go up when the engine is hot. That's just normal expansion. As for your other issue, I would try replacing the thermostat. Hope this helps 🤞