2026-08-15 · 5 min read
BMW 3 Series Oil Leak Malaysia — N20/B48
N20 common oil leaks: valve cover gasket (soaks ignition coils causing misfires), oil filter housing gasket, and crankshaft rear main seal. B48: oil separator hose cracking. Malaysia repair: valve cover RM 400–700, oil filter housing RM 500–900.
Common Oil Leak Points by Engine
- N20: valve cover gasket — oil soaks onto ignition coils (causes misfires)
- N20: oil filter housing gasket — drips onto front of engine
- B48 (G20): oil separator hose — creak and oil mist around air intake
- B48: cam cover gasket — oil drips onto exhaust
Oil on Coils — Act Immediately
Valve cover gasket failure on the N20 typically directs oil onto the ignition coil boots. Oil-contaminated coil boots cause misfires and P030X fault codes — which are often misdiagnosed as faulty coils. Replacing coils without fixing the gasket means the new coils fail within weeks. Always inspect the valve cover gasket when diagnosing ignition misfires.