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Q: Coolant coming out the cap causing smoking when driving i dont know why

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Coolant tant looks full on the out side but when i open the cap i dont see anything so i put water in the tank ..and then when i drive car smokes but its because water/coolant coming for the Cap
My car has an automatic transmission.

Hi there:

The smoke that you’re seeing is evaporated steam caused by an overheating situation. This could be caused by several mechanical issues going on inside your car such as a coolant leak, an obstruction in the coolant lines (like an air bubble or debris), a broken thermostat or water pump issue. If the overflow tank was empty, then its likely that your coolant level was very low or that you might have a leak.

My best advice would be to contact a local ASE certified, such as one from YourMechanic, who might start with a radiator flush and diagnose any other issues that are causing the overheating situation.

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