US set to kill off tech that cuts car engines at red lights

Telegraph

12-05-2025

Car makers could be told to scrap automatic 'stop-start' systems that cut the engine of an idle vehicle as part of Donald Trump's war against red tape.
The automatic feature, which divides opinions among drivers, is designed to conserve fuel and reduce pollution, particularly when driving in traffic jams or stopping at red lights.
It has become common in vehicles around the world as standards for carbon dioxide emissions have been tightened, with regulators tending to give cars that default to the technology better environmental ratings.
But on Monday, Lee Zeldin, head of the US Environmental Protection Agency (EPA), suggested Mr Trump's administration could overturn these rules.
Writing on the social network X, he said: 'Start/stop technology: where your car dies at every red light so companies get a climate participation trophy.
'EPA approved it, and everyone hates it, so we're fixing it.'
It comes after Mr Trump vowed to 'unleash prosperity through deregulation', with one of his executive orders in January stipulating that agencies such as the EPA must now scrap at least 10 regulations for every new one they introduce.
Stop-start systems were first introduced by Toyota in the 1970s and have gradually become more common as environmental standards for vehicle emissions have grown stricter.
They automatically switch off a car's internal combustion engine when it comes to a complete stop, for example at traffic lights, before restarting the engine when the driver signals they want to move again - usually by pressing the brake pedal or the clutch.
They are designed to cut pollution caused by stationary vehicles, with idling linked to 40,000 deaths per year in the UK, according to the Royal College of Physicians.
However, a common question raised by drivers about stop-start systems is whether they risk using more fuel, wearing out the battery or increasing wear and tear on the engine.
The RAC says these are myths, pointing to research showing they can improve fuel economy, and that cars equipped with stop-start technology use sensors to ensure the system only activates when it will not cause damage to the engine. Many also have special, more robust batteries designed for the technology, or separate dedicated batteries.
Still, many drivers still find the systems frustrating, with a previous appeal by the Telegraph to readers finding that many chose to switch them off when they got into their car.
The US EPA encourages car manufacturers to have stop-start systems default to the 'on' position and credits vehicles with better fuel economy ratings if that is the case.
However, Mr Zeldin is a staunch advocate for cutting red tape, arguing that the plethora of rules and regulations that companies must follow creates complexity and adds to the cost of consumer products.
He has dismissed claims that scrapping limits on power station emissions such as soot will do more harm than good and has threatened to overturn regulations in California designed to ban the sale of petrol cars.
'We want to make sure that Americans have access to clean air, land, and water,' Mr Zeldin said he told Fox Business Network in March.
'That's the first pillar of powering the great American comeback. But while we are doing that, we need to unleash energy dominance, pursue permitting reform, make America the [artificial intelligence] capital of the world, bring back those American auto jobs.
'The American public spoke loud and clear that they want this economic relief, and at the end of the day, that's what we're talking about here.'