As a BMW only salvage yard we see a lot of blown motors. We have compiled this list of some of the more common issues seen for each motor.

M30 (1968-1994)

• Oil leaks from valve cover and oil pan gaskets
• Timing chain tensioner failures
• Cracked exhaust manifolds
• Fuel injection system problems (particularly on later models)
• Water pump failures
• Head gasket issues at high mileage

M20 (1977-1993)

• Timing belt failure (particularly on earlier models)
• Head gasket issues
• Cracked cylinder heads
• Oil leaks from valve cover gasket and timing case
• Coolant leaks from water pump
• Worn timing belt tensioner

M44 (1996-2001)

• Cooling system failures (radiator, water pump, thermostat)
• DISA valve failures
• Valve cover gasket oil leaks
• Crankcase ventilation system issues
• Thermostat housing cracks
• Intake manifold gasket leaks
• Fuel injector issues
• Distributor cap and rotor failures (early models)

M52 (1994-2000)

• Nikasil cylinder lining issues (early models, especially US market)
• VANOS seal failures
• Oil separator/PCV valve failures
• Cooling system failures (water pump, thermostat, expansion tank)
• Vacuum leaks
• Cracking plastic intake manifold parts

 

S52 (1996-1999, US-specific)

• VANOS failures
• Cooling system weaknesses
• Rod bearing failures (less common than in S54)
• Oil pump nut backing off
• Chain tensioner failures
• Valve cover gasket leaks

S62 (1998-2003)

• VANOS system failures
• Timing chain guide failures
• Oil pump drive failures
• Valve cover gasket leaks
• Rod bearing wear (less severe than S65/S85)
• Secondary air pump failures
• Thermostat housing leaks

M57 (1998-2012, Diesel)

• Swirl flap failures (can cause catastrophic engine damage)
• EGR valve clogging
• Vacuum pump failures
• Turbocharger failures
• Fuel injector issues
• Oil cooler and oil filter housing gasket leaks

M54 (2000-2006)

• VANOS solenoid and seals failures
• CCV (Crankcase Ventilation Valve) system failures
• Cooling system issues (water pump, thermostat, expansion tank)
• DISA valve failures
• Oil leaks from valve cover gasket
• Leaking oil filter housing gasket

N62 (2002-2010)

• Valley pan gasket leaks ("valley of death")
• Coolant transfer pipe leaks
• Alternator bracket seal leaks
• Valve stem seal failures causing excessive oil consumption
• PCV valve failures
• Timing chain guide wear
• Valve cover gasket leaks
• Water pump failures
• Ignition coil failures

S85 (2005-2010)

• Rod bearing failures (critical issue)
• VANOS system failures
• Throttle actuator failures
• Oil pump failures
• Valve adjustment issues
• Electronic throttle body failures

N52 (2004-2015)

• Electric water pump failures
• Valvetronic motor issues
• Oil filter housing gasket leaks
• Valve cover gasket leaks
• VANOS solenoid failures
• Lifter tick/lifter failures

S65 (2007-2013)

• Rod bearing failures (a critical issue)
• Throttle actuator failures
• VANOS hub gear bolt failures
• Oil pump issues

N54 (2006-2016)

• High-pressure fuel pump (HPFP) failures
• Wastegate rattle and turbocharger failures
• Carbon buildup on intake valves
• Injector failures
• Water pump failures
• Valve cover gasket oil leaks
• Oil filter housing gasket leaks

N63 (2008-Present)

• Valve stem seal failures causing excessive oil consumption
• Battery drain issues (due to hot-vee design requiring engine-off cooling)
• Coolant leaks from various points
• Turbocharger failures
• Fuel injector problems
• High-pressure fuel pump failures
• Valve cover gasket leaks
• Timing chain guide failures
• Premature spark plug wear
• Spun Rod Bearings

N57 (2008-2019, Diesel)

• Timing chain stretching issues
• EGR system failures
• Swirl flap issues (improved from M57)
• Injector failures
• Glow plug failures
• Oil cooler leaks

S63 (2009-Present)

• Turbocharger failures
• Oil consumption issues
• Valve stem seal degradation
• Timing chain guide wear
• High-pressure fuel pump failures
• Valley pan gasket leaks
• Coolant pipe leaks in the valley
• Water pump failures
• Spun Rod Bearings

N55 (2009-2019)

• Valve cover and valve cover gasket leaks
• Oil filter housing gasket leaks
• Electric water pump failures
• Charge pipe failures (particularly under increased boost)
• Carbon buildup on intake valves
• VANOS solenoid issues
• Spun Rod Bearings

N20 (2011-2017)

• Timing chain failures (critical issue, especially 2012-2014)
• Oil filter housing gasket leaks
• Valve cover gasket leaks
• Vacuum pump failures
• VANOS solenoid issues
• Electric water pump failures
• Carbon buildup on intake valves
• Cracked Cylinder Head

B46 (2014-Present)

• High-pressure fuel pump failures (early models)
• Oil leaks from valve cover
• Cooling system issues
• VANOS solenoid failures
• Occasional wastegate issues
• Oil filter housing gasket leaks

B58 (2015-Present)

• Coolant leaks (early models)
• Oil filter housing gasket leaks
• Valve cover gasket leaks
• Charge pipe failures under high boost (less common than N55)
• Occasional oil cooler failures
• VANOS solenoid issues

S58 (2019-Present)

• Occasional oil cooler leaks
• High-pressure fuel pump issues (early production)
• Charge pipe failures under extreme pressure
• Some reports of rattling turbocharger wastegates
• Oil filter housing gasket leaks
• Cooling system issues