...took it to the garage and I..... think they forget to add some b/c the light came om again. I went to the store this morning to buy some engine coolant. My question is which place do you put it. I notice under the hood there is a metal cap you twist off when the engine is cool. Also there is a plastic reservoir that says coolant. Which place do I add it?

[EagleAutosports]

I would wait till it's cool enough to get the cap off and put it in there.