Cannot start the car, I change the battery and problem continued

Key will not come out not turning to lock position. The car is still on account only way I can get it to turn all the way off is to disconnect battery.

Trax is smelling hot No lights on but coolent was low

Occasional coolant smell and nearly imperceptible coolant loss was traced to the turbo. Over time, maybe 5 ounces of coolant dripped on the indoor garage floor... Inspection of the engine compartment… 

1/2 gal coolant every three wks.gm will pay 1/4. Not acceptable