My bravada overheated and when I punched the gas the gages went down, what could

If you think you have a coolant leak then you can rent a coolant system pressure tester at most auto parts stores. This allows you to pressurize the cooling system with a cold engine so you can search for leaks. If your gauges don't work that's probably another problem altogether. This could be a bad cluster, bad connection, wiring, etc. Hands-on inspection is needed.https://repairpal.com/repair-shops Alex