Want to be an eco-driver but can’t seem to keep the pedal off the metal? Meet Nissan Motor Co.’s ECO pedal, which pushes back against excess foot pressure to encourage fuel-efficient driving. The ECO accelerator will be installed in some Nissan cars starting next year and be accompanied by a real-time dashboard display of fuel consumption. Nissan says the gadget could increase fuel efficiency 5 to 10 percent, and the device can easily be switched off by those who don’t like Big Brother watching their lead foot. But the initial response from car enthusiasts is skepticism. “This may be one of the worst ideas we’ve yet heard of,” says car blog Jalopnik, noting concern about “what will happen when a driver needs to overtake another vehicle at high speed on a highway” and concluding, “This feature needs to die before it even hits the streets.”