What are the causes of oil burning in the Peugeot 1.8T engine?
2 Answers
The causes of engine oil burning are as follows: 1. Aging of valve stem seals: Due to temperature reduction, the rubber material of the valve stem seals becomes stiff, resulting in incomplete sealing. Oil leaks into the combustion chamber from the valves and burns. When the car has not fully warmed up, the engine exhaust emits significant blue smoke, but this normalizes after the engine reaches operating temperature. 2. Poor piston ring sealing: Due to faulty piston ring sealing, oil is directly drawn into the combustion chamber through the leaking piston rings under the action of the oil pump. Even when the car reaches normal operating temperature, the exhaust pipe continues to emit blue smoke.
I've repaired quite a few Peugeot 1.8T engines, and oil burning is quite common. The main reason is some design flaws in the piston rings of that engine, which are prone to wear or deformation under high temperatures, causing oil to seep into the combustion chamber and burn. Another major issue is poor sealing in the turbocharger, where oil can leak from. Also, pay attention to the PCV system—if the crankcase ventilation valve gets clogged, increased internal pressure can cause oil to flow back into the intake pipe. All these factors accelerate oil consumption. If ignored long-term, the engine will suffer from more severe carbon buildup and even cylinder damage. I recommend regularly checking the oil level and replacing the seals if you notice oil loss. Addressing these issues early can save you a lot of money.
