Hey everyone
Wanted to see if there was a chance for another explanation of bubbling coolant. 50/50 mix. Radiator fan always on (on purpose) on the highway heats to just a bit past half in over 90 degree weather and ac on. No oil in coolant or vice versa. No loss of power that I notice and no loss of coolant? I added water wetter this week because it got pretty hot on the highway and that keeps it down to half all the time.

Before I assume bad head gasket.. Any other things that may cause this?

 

Why would you assume a bad head gasket? Maybe you have a bad thermostat or a lot of debris in between the condenser and radiator, or maybe a plugged radiator. Stock, these cars run hot. That's how the GM engineers designed them. How hot is "a bit past half" ?

 

One mechanic says head gasket is blown. Other doesnt. Anytime its brought in. Brand new thermostat, radiator cap and coolant. The debris is possible but the radiator is new sadly

 

Well if you aren't losing coolant anywhere, how could the head gasket be bad? What temp thermostat are you using?

 

From what I was told the combustion chamber is leaking pressure. On the highway it is 2 or so ticks past half. Before my radiator fan was wired on all the time it got about 4-5 ticks past. Very cool thermostat. I'll have to see which temp I got. It was the lowest the store had

 

Sounds to me like nothing whatsoever is wrong with your engine or coolant system, except that you need a NEW radiator cap.

Replace the rad cap.

 

I forgot to mention when I first noticed this, that's what I replaced. Brand new cap

 

If your cylinders are leaking pressure, that could be other issues like bad rings or a bad valve. You also realize that a stock temp gauge isn't the most accurate if it's reading "ticks". I would start with a cooler thermostat and a new cap (which has been mentioned), and make sure your air dam is functional underneath the car, and also make sure the radiator is clean (on both sides) Just cause a cap or thermostat is new, doesn't mean it's any good either. Have the cap pressure tested.