Engine light came on but car is still running great

U need to have codes read w/ scanner tool. Most parts stores will do this free, and give u some advice as to why the engine light came on. The van may run fine, but u could be causing damage to a component or system. An example would be code for 'engine misfire', car runs fine, same gas mileage, no trouble starting, etc, but it was a problem w/ fuel injectors, by ignoring the light, catalytic converter was damaged, so have it checked out before it develops into a bigger problem. Good Luck