Emission System Warning Light

First thing is to get your vehicle scanned for codes, most auto parts places will do it for free, make sure you get the code numbers, secondly, do not blindly start replacing pieces, it's a waste of $$$$$. After the issue is resolved, the light will turn itself off after a pre-determined number of warm-up cycles, depending on the part, as amany as 40 warm-ups. Or you can have someone with a scan tool turn the light off, when you turn the light off, it also resets all the vehicle emission control monitors back to "not ready status", one reason why turning the light off if your state has emission testing, the car will fail if all the monitors have not run. I recommend that you spend a few bucks and buy your own obdII reader, anywhere from 70 on up, depending on complexity, you can find out a lot from using one, read up on the systems they're quite interesting, as long as everything is working correctly. You can still drive, the vehicle just won't be at optimum, system is designed to compensate for failed pieces, however not at best efficiency, failure effects management mode, femn as it's known, is programmed into all systems, good luck