BMW Buyer's Guide

Comprehensive Used Car Analysis
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1 Series F20 / F21
1 Series F20 / F21
1 Series F20 / F21
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1 Series F20 / F21

F20 • 2011–2019 • Hatchback
Engines: 4 Issues: 14 Reliability: 74%
4
Engine Options
14
Known Issues
2
Critical Issues
74%
Reliability Score

Facelift (LCI) – 2015

  • Full LED headlights available
  • Revised front and rear design
  • Updated iDrive with touchscreen
74% – Good

Engines

B38B15 – 1.5L 3-Cylinder Petrol

116i, 118i • 109–136 hp • 180–220 Nm
Displacement 1.5L
Layout I3
Fuel Petrol
Transmission 6-Speed Manual (Getrag), 8-Speed Automatic (ZF 8HP)
Modular engine architectureTwinPower TurboValvetronic IVDouble-VANOSDirect injection
Known Issues1 issue
medium Coolant Loss Moderate (~20%)
Minor coolant leaks from thermostat housing or water pump area.
Typical Mileage
60,000–100,000 km
Est. Repair Cost
€200–€500
DIY Friendly
✓ Yes
Low coolant warningSweet smell from engine bay

N20B20 – 2.0L Turbo Petrol

120i, 125i • 177–218 hp • 270–310 Nm
Displacement 2.0L
Layout I4
Fuel Petrol
Transmission 6-Speed Manual (Getrag), 8-Speed Automatic (ZF 8HP)
TwinPower Turbo (twin-scroll)Valvetronic IIIDirect injectionDouble-VANOS
Known Issues4 issues
critical Timing Chain Stretch Common (>30%)
The N20 timing chain and guides wear prematurely, causing rattling and potential engine failure if ignored. Particularly common on earlier production units.
Typical Mileage
60,000–120,000 km
Est. Repair Cost
€1,500–€3,000
DIY Friendly
✗ Specialist
Rattling on start-upCheck engine lightRough idleRough running
critical Oil Pump Failure Occasional (~15%)
Oil pump drive can fail leading to complete oil pressure loss. Catastrophic engine damage results.
Typical Mileage
80,000–150,000 km
Est. Repair Cost
€2,000–€6,000+
DIY Friendly
✗ Specialist
Oil pressure warningEngine knockSudden power loss
medium Charge Pipe Failure Common (>30%)
The plastic charge pipe cracks under boost pressure, causing a sudden loss of power. Aftermarket aluminium upgrades available.
Typical Mileage
50,000–100,000 km
Est. Repair Cost
€100–€250 (aftermarket upgrade)
DIY Friendly
✓ Yes
Boost lossWhistling noiseLimp mode
medium Coolant Loss at Thermostat Common (~30%)
Thermostat housing cracks or gasket leaks, causing slow coolant loss.
Typical Mileage
60,000–100,000 km
Est. Repair Cost
€200–€400
DIY Friendly
✓ Yes
Low coolant warningPuddle under carOverheating

N55B30 – 3.0L Turbo Petrol

M135i, M140i • 326–340 hp • 450–500 Nm
Displacement 3.0L
Layout I6
Fuel Petrol
Transmission 6-Speed Manual (Getrag), 8-Speed Automatic (ZF 8HP)
TwinPower Turbo (twin-scroll single turbo)Valvetronic IIIDirect injectionDouble-VANOSElectric water pump
Known Issues4 issues
medium Charge Pipe Blow-Off Common (>35%)
Factory plastic charge pipe blows off under high boost, particularly in warm weather or spirited driving. Aftermarket aluminium replacement recommended.
Typical Mileage
40,000–80,000 km
Est. Repair Cost
€100–€250
DIY Friendly
✓ Yes
Sudden power lossBoost leak whistleLimp mode
high Valve Cover / VANOS Gasket Leak Common (>35%)
Valve cover and VANOS solenoid gaskets seep oil over time. Oil can drip onto hot exhaust components causing burning smell and smoke.
Typical Mileage
60,000–120,000 km
Est. Repair Cost
€300–€700
DIY Friendly
✓ Yes
Burning oil smellVisible oil seepageSmoke from engine
high Oil Filter Housing Gasket Leak Common (>35%)
Oil filter housing gasket deteriorates and leaks oil onto belts and other components.
Typical Mileage
60,000–100,000 km
Est. Repair Cost
€250–€400
DIY Friendly
✓ Yes
Oil leakBurning smellOil on engine
high Electric Water Pump Failure Common (~30%)
Electric water pump fails causing overheating. Shared issue with other N-series inline-6 engines.
Typical Mileage
80,000–130,000 km
Est. Repair Cost
€400–€700
DIY Friendly
✓ Yes
OverheatingWarning lightNo heat from vents

B47D20 – 2.0L Diesel

116d, 118d, 120d • 116–190 hp • 270–400 Nm
Displacement 2.0L
Layout I4
Fuel Diesel
Transmission 6-Speed Manual (Getrag), 8-Speed Automatic (ZF 8HP)
Modular engine architectureCommon-rail solenoid injectionVariable geometry turboAluminium blockFront-mounted timing chain
Known Issues3 issues
high EGR Cooler Leak Moderate (~20%)
EGR cooler can develop internal leaks, mixing coolant into the exhaust system.
Typical Mileage
80,000–150,000 km
Est. Repair Cost
€500–€1,000
DIY Friendly
✗ Specialist
Coolant lossWhite exhaust smokeOverheating
medium Injector Seal Leak Moderate (~25%)
Copper injector seals deteriorate, causing a black tar-like residue around injectors and diesel smell.
Typical Mileage
80,000–130,000 km
Est. Repair Cost
€200–€400
DIY Friendly
✓ Yes
Diesel smellBlack residue around injectorsRough idle
medium EGR Valve Clogging Common (~30%)
EGR valve clogs with carbon, especially on cars doing mostly short trips.
Typical Mileage
80,000–130,000 km
Est. Repair Cost
€300–€600
DIY Friendly
✓ Yes
Reduced powerRough idleEML light

Common Issues (F20-specific)

Electrical 1

medium Tailgate Wiring Harness Failure Common (>30%)
Wiring in the tailgate harness breaks due to repeated opening, causing rear light and wiper failures.
Typical Mileage
50,000–100,000 km
Est. Repair Cost
€150–€350
Category
Electrical
Rear lights outWiper failureBoot not closing properly

Drivetrain 1

low Driveshaft Vibration Moderate (~20%)
Center support bearing and guibo (flex disc) wear cause driveline vibrations.
Typical Mileage
80,000–140,000 km
Est. Repair Cost
€300–€600
Category
Drivetrain
Vibration at speedClunking on accelerationRumbling noise

Wear Items

B38B15 – Wear Items

116i, 118i

Spark Plugs Every 60,000 km
NewReplace
Replacement Cost€60–€100
Wear Factor55%

N20B20 – Wear Items

120i, 125i

Spark Plugs Every 60,000 km
NewReplace
Replacement Cost€80–€150
Wear Factor55%
Turbo Wastegate Rattle Fix 60,000–100,000 km
NewReplace
Replacement Cost€100–€300
Wear Factor45%

N55B30 – Wear Items

M135i, M140i

Spark Plugs Every 45,000 km
NewReplace
Replacement Cost€100–€180
Wear Factor60%
Ignition Coils 80,000–120,000 km
NewReplace
Replacement Cost€200–€400
Wear Factor50%

B47D20 – Wear Items

116d, 118d, 120d

DPF (Diesel Particulate Filter) 150,000–250,000 km
NewReplace
Replacement Cost€800–€2,000
Wear Factor40%
Glow Plugs 80,000–120,000 km
NewReplace
Replacement Cost€100–€250
Wear Factor45%

All Variants

All Variants

Complete list of model variants for F20 / F21

ModelEngineDisplacementLayoutPowerTorqueTransmission
116i B38B15 1.5LI3109–136 hp180–220 Nm Manual, Automatic
118i B38B15 1.5LI3109–136 hp180–220 Nm Manual, Automatic
120i N20B20 2.0LI4177–218 hp270–310 Nm Manual, Automatic
125i N20B20 2.0LI4177–218 hp270–310 Nm Manual, Automatic
M135i N55B30 3.0LI6326–340 hp450–500 Nm Manual, Automatic
M140i N55B30 3.0LI6326–340 hp450–500 Nm Manual, Automatic
116d B47D20 2.0LI4116–190 hp270–400 Nm Manual, Automatic
118d B47D20 2.0LI4116–190 hp270–400 Nm Manual, Automatic
120d B47D20 2.0LI4116–190 hp270–400 Nm Manual, Automatic