What are the reasons for Audi cars burning engine oil?
2 Answers
Audi cars burning engine oil can be attributed to the use of inappropriate oil viscosity, the engine's negative pressure design, and engine carbon buildup. Below are detailed explanations and solutions: Use of inappropriate oil viscosity: Audi cars are high-end German vehicles, and it is best to use fully synthetic oil. The oil viscosity should preferably not be below 30, with the minimum requirement being 5W40 oil. Using oil with too low viscosity can also lead to oil burning. Engine's negative pressure design: Audi models feature a negative pressure engine design. During operation, the crankcase is in a vacuum state, causing excessive crankcase exhaust gases to enter the engine's intake system. While expelling exhaust gases, some atomized oil in the crankcase also enters the intake manifold along with the exhaust gases, resulting in significant engine oil loss. Engine carbon buildup: Due to the difference in domestic fuel quality compared to international standards, a large amount of carbon buildup can easily form in the combustion chamber during engine operation. This carbon buildup deposits in the piston grooves, causing the piston rings to stick together. As a result, the piston rings cannot seal completely, and the "stuck" piston rings greatly reduce their oil-scraping and sealing capabilities. Additionally, sludge can clog the oil return holes, preventing oil from returning normally and leading to increased oil consumption. This results in the phenomenon of Audi cars burning engine oil, necessitating the cleaning of engine carbon buildup.
As a mechanic who frequently services Audis, I've seen the most common causes of oil burning. Piston ring wear is the number one issue. The design of piston rings in certain Audi engines isn't very heat-resistant, and prolonged driving in congested areas can easily lead to clogged ring grooves and poor sealing, allowing oil to seep into the combustion chamber and burn off. Aging valve guide seals are also a frequent occurrence, especially in cars with over 100,000 kilometers. Insufficient elasticity in the seals can cause oil leaks. If the turbocharger has excessive blade clearance or oil leaks, it directly introduces oil into the intake system. Another issue is PCV valve system failure. Audi's exhaust gas recirculation system is very precise, and if the valve gets clogged or the pipes crack, oil vapor can't be properly recycled, leading to additional consumption. When encountering oil burning, promptly checking these components is crucial to save on repair costs. Additionally, carbon buildup is also an accomplice, especially when using low-quality gasoline, as engine deposits can compress piston rings and accelerate wear. With proper maintenance, Audi's oil burning issues can be significantly alleviated.
