radiator cap

its on your reservoir tank see pic

That's thing I know where my overflow tank is but not my reserve tank. I need to know cause I have gasket fixer and I have to put it in my radiator an overflow

it isn't actually your overflow tank it's the surge tank, if you put it in there as it 's pressurized it will get into the system as you drive. You are much better off fixing the actual problem than putting that stuff into your cooling system

read the guide guide below, it may help

https://www.2carpros.com/articles/car-is-leaking-coolant

The diagram below shows the surge tank

Thanks I'll try that now