2000-2005 Chevy Impala Monte Carlo Sunroof Button Switch. Works on 2040-parts.com

London's GPS-based speed-limit trial puts Big Brother's foot on the gas pedal

A fleet of 12 Toyota Priuses in London have been fitted with GPS-linked speed limiters to measure how drivers respond to having their speed controlled by a computer rather than their own feet. For now, the trial is local to London, run by Transport for London, the agency that manages the city's roads, buses, subways and trains. The agency is using its own fleet of Priuses for the test and will add a bus and a taxi later this year.

Chevrolet Volt prices announced

GM has revealed that the Volt hybrid could cost $33,500 (£21,000) in the US after government tax credits, making it nearly £2000 cheaper than Nissan’s Leaf electric car. The Volt’s List price is $41,000 (£26,300) but qualifies for a subsidy thanks to its low emissions. A basic Volt comes with Bluetooth and sat-nav but buyers can add leather seats and steering wheel, heated seats, rear camera, polished wheels and park assist.

VW halts merger talk with Porsche

Volkswagen on Sunday slammed the brakes on merger talks with Porsche, just before the first meeting to discuss ways to bring all of the automakers' brands together under one entity. VW said that it made the move because it believes that Porsche doesn't have a solid plan for the merger. VW and Porsche announced the plan to hold merger talks on May 6.