Just like the fatty plaque that builds up inside the heart’s blood vessels and can prove fatal, engine sludge can cause ‘premature death’ of vehicle engines.

This black sludge, similar to heavy grease or tar, results from oxidation and thickening of the engine oil.

It can block the engine’s lubricating system and internal oil passages preventing proper oil flow and, in the worst case, cause engine seizure.

In many cases, the problem will go undetected until the engine develops a major problem and is then dismantled for assessment.

So why does it form?

The most common cause is related to inadequate servicing such as missed or extended (past the maker’s schedule) oil change intervals.

Poor quality oil or inappropriate oil (i.e. oils that don’t meet or exceed the maker’s specification) can also be a major factor.

Engine oil thickening/gelling in diesel engines can result from fuel contamination of the oil due to fuel system problems such as worn/leaky injectors.

Fuel system maintenance is vital.

So, have the oil serviced as scheduled based on time or distance travelled, whichever occurs first, and only use good quality oil and filters.

More frequent oil changes will be specified under conditions the manufacturer defines as ‘severe’, including typical city driving. Follow the maker’s instructions.

The proverbial ounce of prevention really is better than the pound of cure.