Drivers are just discovering dashboard button that can boost their motor’s power in seconds – but there’s a costly catch

A MECHANIC has revealed a little-known dashboard button that can boost your motor's power in seconds.

The switch doesn't actually affect the engine at all but makes a subtle change which allows it to access hidden speed.

Scotty Kilmer, who has over 50 years of experience in the car industry, showed Brits how to use the button on his YouTube channel.

It is usually marked with the letters ECT or the words "ECT Power".

That stands for electronically controlled transmission and changes the way that you shift gears.

Scotty explained: "Does it mean that rockets are going to come out the back and you'll shoot up the road?

"No but it will shift later to give more power.

"Your engine goes to higher RPMs for more power."

You can tell when the system is active when the letters ECT light up on the dial cluster, usually on the speedometer.

This works on automatic cars, meaning that around nine million Brits could have the button in their vehicles.

As Scotty said, it forces the transmission to shift up later, allowing the engine to hit higher revs and access more power and better acceleration.

The equivalent effect can still be achieved in a manual car, simply by choosing to delay the gear change until a higher rev count.

However, Scotty did warn of a costly catch of the move.

He added: "You get worse fuel mileage.

"And of course, the engine will wear out slightly faster because it's spinning faster."

It comes after drivers were handed an urgent travel warning over the M25 weekend shutdown.