What Causes Low Cylinder Pressure in BMW N46 Engine?

[AubreeRose]

BMW N46 engine's low cylinder pressure is caused by increased combustion chamber volume, reduced air intake, and deteriorated sealing. Reduced air intake: The engine's air intake determines the amount of gas compression before the piston reaches top dead center at the end of the compression process, thereby determining the gas pressure. Causes of insufficient engine air intake include clogged air filters, incorrect valve opening height in variable valve lift systems, and misalignment between crankshaft and camshaft in valve timing. Increased combustion chamber volume: After prolonged use, excessive carbon deposits on piston surfaces may lead to excessively small compression ratios and increased combustion chamber volume. Deteriorated cylinder sealing: Poor cylinder sealing makes gas leakage more likely, similar to how engine oil leaks occur.