Oil Leaks
Oil Leaks
Section titled “Oil Leaks”As the E46 ages, oil leaks become increasingly common. Here are the most frequent sources.
Common Leak Locations
Section titled “Common Leak Locations”Valve Cover Gasket
Section titled “Valve Cover Gasket”- Symptoms: Oil seepage on sides of engine, burning oil smell
- Part: 11 12 7 588 412 (includes spark plug tube seals)
- Torque: 10 Nm (aluminum — do not overtighten)
Oil Filter Housing Gasket
Section titled “Oil Filter Housing Gasket”- Symptoms: Oil drip from front-center of engine
- Gasket: Located between oil filter housing and engine block
- **Common to leak after careless filter changes
Oil Pan Gasket
Section titled “Oil Pan Gasket”- Symptoms: Oil drip from bottom of engine, oil on subframe
- Part: 11 13 7 548 031
- Repair: Requires subframe lowering or removal for access
VANOS Solenoid Seals
Section titled “VANOS Solenoid Seals”- Symptoms: Oil on top of valve cover near VANOS solenoids
- **O-rings harden and leak with age
Rear Main Seal
Section titled “Rear Main Seal”- Symptoms: Oil between engine and transmission
- Repair: Requires transmission removal — often done with clutch replacement
Prevention
Section titled “Prevention”- Regular oil changes with quality oil and filter
- Don’t overfill oil level
- Replace gaskets proactively at major service intervals