Symptom: a Bora 1.8T, the engine oil to the upper limit of the dipstick, the vehicle after driving 1000km back to the service station, add oil 450ml.

     Inspection and analysis: According to the specific structure of the car analysis, resulting in high engine oil consumption for five reasons: ① valve oil seal oil. ② piston and cylinder tube seal is not strict. ③ crankcase forced ventilation PCV valve failure. ④ turbocharger oil seal oil spill. ⑤ engine oil pan liner, oil seal, etc. leakage.

     Watch the engine outside the oil traces of oil, indicating that the oil is reduced into the cylinder consumption. According to past experience, if the turbocharger oil seal oil leakage, in the intercooler will accumulate a lot of oil, so the engine turbo increased by the turbocharger. The oil seal is not damaged. According to the exhaust pipe no obvious blue smoke phenomenon, indicating that most of the consumption of oil in the engine was heated and become coke, and then suspected valve oil seal leakage. Remove the four injectors with endoscopic observation of the intake valve and found a cylinder on the back of the valve there are a lot of coke, which is judged to be a cylinder into the valve oil seal damage.

     Troubleshooting: As the user asked to reduce maintenance costs, we decided to replace only one valve seal, and the use of non-cylinder valve door valve repair method. Then remove the valve chamber cover and the first cylinder spark plug, the crankshaft rotation to the first cylinder compression stroke at the top of the point, to the first cylinder filled with compressed air, remove the camshaft replaced the first cylinder intake valve seal. After the vehicle is delivered to the user and the phone is tracked, the user reflects that there is no shortage of oil between the 2 times for oil maintenance.