Mechanics issue warning that common driving bad habit can cause car engine 'black death'

Mechanics have warned that one simple mistake could lead to complete petrol and diesel engine failure in a major blow. Experts at Bumper stressed that the accumulation of carbon deposits, which are a by-product of unburnt fuel and poor engine circulation, can clog internal components.

Often referred to as the Black Death, the build-up of deposits can dramatically reduce fuel efficiency and eventually break engines. Those living in built-up areas and content to stay around their city are most at risk of picking up the serious issue. This is because the issue is more prevalent in those who drive at "low speeds" and consistently run "short journeys."

A spokesperson for Bumper said: "If you're constantly driving at low speeds - especially for short journeys - your engine never gets hot enough to burn off carbon deposits. Over time, this can lead to a build-up inside your valves, pistons and exhaust system."

They added: "In the worst-case scenario, carbon build-up can cause your engine to seize - and replacing that could cost thousands. Modern engines are designed to be run at higher speeds from time to time. Taking your car for a steady drive on the motorway helps heat the engine fully and allows fuel to clean and lubricate components."

Breakdown specialists at the AA have previously warned that a car's Diesel Particulate Filter (DPF) can become blocked up if motorists are doing lots of small journeys.

A blocked filter can lead to reduced power and engine performance, higher fuel consumption and even possibly engine damage.

In severe cases, vehicles may enter 'limp mode' which can restrict vehicles to a maximum of 40mph. The AA stressed that a weekly run up the motorway should stop filters from becoming blocked, again stressing the importance of putting vehicles through their paces once in a while.

Specialists at Redex Additives also explained: "If you only ever use your car for quick trips, the DPF may not reach the temperature needed to regenerate, causing a blockage that could lead to a breakdown.

"So, if you drive a diesel, you should always make sure to take longer journeys every so often to keep your DPF clean and in good working order.

"If you see the DPF warning light, take your car on a longer, faster journey to clear the blockage; getting up to motorway speed works best."