So on my 97 4.6l I've had an overheating issue.

It only happens when the car is warming up, right before it gets to running temp it jumps straight up to red line. (Seems as though the termostat isn't opening up properly). Once the engine temp levels out it doesn't happen again. Every once in a while when it overheats it also pushes coolant out of the overflow. Edit: sometimes this will happen 5 or so times before it levels out. Usually a couple miles into driving, and then in rapid succession after that.

I have replaced the thermostat 3 times now, am on my 3rd radiator cap, also have replaced the radiator, water pump, and intake hoses and gaskets, and sensor. I have also bled the system countless times and flushed it about three times.

When I turn the fan on for my heat I do breifly smell antifreeze but there are no leaks in the cab or visible on the heater core (I cut a hole behind my glove box to open my blend door which gives me a pretty good line or sight to my heater core.)

I'm not blowing any smoke, nor do I see any coolant in my oil, or any bubbles in my coolant (though I have been meaning to test for combustion gases in it)

PLEASE HELP!?

Also: sometimes when it "overheats" it returns right back to running temp upon restart, other times it takes 10 min or so to gradually go down. I'm convinced there is air getting into the lines somewhere but I'm not sure how or where