How long before you run out of gas when check gauges come on 2002 Chevy cavalier?

The "check gauges" light in a 2002 Chevy Cavalier doesn't specifically indicate how much gas is left. It's a general warning light that something is amiss with your gauges, which *could* include the fuel gauge. It doesn't mean you're necessarily low on fuel, though that's a possibility.

If your fuel gauge is also showing empty or very low, you likely have very little fuel remaining – perhaps only 1-2 gallons, or even less. Driving on fumes can damage your fuel pump. It's best to fill up immediately when the fuel gauge nears empty, regardless of the "check gauges" light. The exact range will depend on your driving habits and the car's condition.

Do not rely on how far you think you can go. Find a gas station as soon as possible.