Turbocharged trouble: Why skipping downshifts harms your engine

The almost ubiquitous turbochargers, which provide "strong low-end torque" (and meet emissions standards), have become the main reason for driver errors. When the road is clear and the car seems to accelerate adequately just by pressing the gas pedal, we tend to skip downshifting. However, this is a mistake that negatively affects the engine.

Many drivers believe that accelerating at lower RPMs is better due to less noise from the exhaust system. Nonetheless, the engine is not designed to handle heavy loads at low RPMs. Under these conditions, its efficiency decreases—energy from the fuel is more dedicated to generating heat than actual acceleration. This results in higher fuel consumption and engine heating, especially the inside of the cylinders.

Excessive heating of these components can lead to uneven fuel mixture combustion and ignition problems. As a result, forces in the cylinder become unevenly distributed, contributing to faster engine wear. Turbocharged engines, found in most new cars, are particularly sensitive to such acceleration, increasing the risk of premature ignition of the mixture.

Research conducted by Japanese companies Toyota and Denso has shown that glowing remnants of fuel and oil can remain in the engine when accelerating without downshifting. Such particles at low RPMs increase the chance of uncontrolled ignitions, which shortens the lifespan of pistons and spark plugs.

Driving instructors also recommend downshifting before accelerating during courses. Overtaking is a risky maneuver that requires a dynamic, swift conclusion. Downshifting allows you to utilize the vehicle's full capabilities and quickly complete the overtaking manoeuvre.