Possible Causes Of Increased Engine Oil Consumption

Measurement errors when measuring the oil level => 

• Vehicle is not parked horizontally. The same measuring station is not always used.
• Tyre inflation pressure is very different.
• Vehicle centre of gravity is not consistent (imbalanced load).
• Incorrect engine oil test temperature.
• Engine oil level measured too soon after stopping engine (allow sufficient time for oil to flow back completely into oil pan!).
• Incorrect reading of oil dipstick or instrument cluster.

Important and often disregarded factors relating to engine oil consumption => 

• Driver profile:  Vehicles that are used for very sporty driving tend to use more engine oil than vehicles driven normally.
• Driving conditions:  Frequent cold starts/driving short journeys result in a higher percentage of fuel in the engine oil (oil is diluted). If the same vehicle is then driven until it gets hot, the fuel in the engine oil evaporates and the engine oil level drops.
• Engine run-in:  The components are "run in" during the first 10, 000 kilometres/6, 000 miles (even in modern engines). This can increase oil consumption. After 10, 000 km/6, 000 miles, oil consumption should level off to a lower level.
• Engine load:  Engine oil consumption can increase during long motorway journeys in the summer, when pulling a trailer, or when driving over high mountain passes for example.
• Loss of engine oil:  The engine is leaking and loses oil (possibly onto the underbody panelling).
• Fuel quality:  Small amounts of diesel, bio-fuel (ethanol) or bio-diesel in the petrol (e.g. contamination as a result of using the same fuel tanker for diesel/petrol) affect how it enters the oil and how it is evaporated.