Just replace battery and alternator. Car is overheating and smoking. Do you know what is causing this?
Battery/alternator have nothing to do with overheating. You have to go through all the basic stuff that can cause overheating - check coolant levels, check hoses, check radiator cap, check thermostat, check operation of water pump, check operation of coolant temperature sensor, flush/refill, check for blockages, check for trapped air, etc. The 'smoke' may have been steam from overheating, although you should confirm that. If you have steam it's either a leak or overflow boiling over.
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