Roland Piquepaille writes "This might soon be possible according to researchers at the University of Manchester. They've designed a near-infrared diode laser sensor able to record levels of carbon dioxide, carbon monoxide and methane directly from your car's exhaust. Their device could be one day incorporated into onboard diagnostic systems and be permanently in use while you drive. So you could be warned that your pollution levels are too high. The system would include dashboard warnings telling you to modify the way you're driving. But read more for additional details and a picture of the test bed the researchers used to take their measurements."