Oil consumption test: General

Some oil consumption is normal when an engine is running. The oil consumption varies depending on different factors:

• The condition of the engine (how well the engine is maintained)
• Blocked or damaged air filter
• Driving conditions - large loads, or excessive idling
• Oil grade and viscosity
• Cylinder capacity - in general a larger motor consumes a greater amount of oil than a smaller engine
• Engine power - a stronger engine consumes more oil than a smaller powered engine
• Oil level - too high a level (above the maximum mark on the dip stick) results in increased oil consumption.

Normal oil consumption 

Running-in period 

The oil consumption can be as much as 1 liter per 1,000 km during a running-in period of approx. 5,000 km if the engine is new or replaced (replacement of piston ring).

Driving between 5,000 and 150,000 km 

Normal driving: up to 0.25 liters per 1,000 km is considered normal oil consumption.

Driving at high speed/with heavy trailer: up to 0.40 liters per 1,000 km is considered normal oil consumption.

Mountain/alpine driving: up to 0.50 liters per 1,000 km is considered normal oil consumption.

The above stated values for oil consumption can be used as guidelines if there is a suspicion that oil consumption is unusually/abnormally high.

To determine the exact oil consumption a test drive of at least 1,000 km must be performed under controlled conditions. The oil must be weighed before and after the test drive. This way the exact oil consumption can be calculated.

Abnormally high oil consumption 

If the customer points out that the car consumes an abnormal amount of oil, the checks below must be carried out before carrying out corrective action.

• Ask the customer what their driving conditions are (see General causes of high oil consumption )
• Check for oil leaks
• Check that the crankcase ventilation is not blocked
• Check that the correct dip stick is in the engine. Check that the dip stick is pushed down as far as possible
• The car must be parked on level ground when measuring the oil. The engine should be driven at normal operating temperature on the road (not idling) for 30 minutes. The engine must then be left for 15 minutes before noting the oil level.