Modern internal combustion engines rely on precise sensor calibrations and tight mechanical tolerances. Skipping routine servicing leads to component friction, carbon deposits, and incomplete fuel combustion that steadily degrades your MPG.

1. Correct Engine Oil Viscosity & Quality

Engine oil lubricates pistons, camshafts, and bearings under extreme thermal stresses. Over time, oil degrades, oxidises, and gathers soot particles, increasing internal friction. Using the exact manufacturer-specified viscosity (e.g. 0W-20, 5W-30) and fully synthetic oils can improve fuel economy by 1% to 2% compared to using the incorrect grade.

2. Air Filters & Mass Airflow (MAF) Sensors

A clogged air filter restricts the volume of oxygen entering the combustion chambers. In modern electronic fuel-injected cars, the engine computer compensates by adjusting the fuel injection pulse, which can cause sluggish acceleration and poor throttle response. Replacing an air filter costs under £20 and takes less than five minutes.

3. Spark Plugs & Ignition Coils

In petrol vehicles, worn spark plugs with eroded electrodes produce weaker sparks, resulting in incomplete fuel combustion (misfires). Up to 10% of injected fuel can pass unburnt into the exhaust system, damaging expensive catalytic converters and significantly reducing miles per gallon.