It started off sucking in too much antifreeze but not overheating. Now the meter quickly rises to hot especially while idling. Sometimes it sucks in all of the antifreeze in one day and sometimes the line doesn't drop for days, but still says it's overheating. No sign of leaking, no antifreeze smell, the heat hasn't been reliably working and the engine is still cold when I turn it off and open the hood. Also on some starts my electronic throttle control pops up. Any advice is much appreciated.