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BMW B38 / B37 vs 1.2 16v: which engine is more reliable?

According to our risk index, the BMW B38 / B37 carries less risk than the 1.2 16v: 14/100 (low risk) versus 36/100 (moderate risk). The BMW B38 / B37 has 1 documented serious fault, the main one being «B38 crankshaft thrust bearing failure (units before April 2015)»; the 1.2 16v has 1 documented serious fault, the main one being «Damaged head gasket and coolant loss».

Risk index

BMW B38 / B37

14

Low risk · 1 serious fault

Lower risk

Risk index

1.2 16v

36

Moderate risk · 1 serious fault

The index (0–100) weights the severity and frequency of the three most serious documented faults. How it is calculated

21 sourcesHow we work

Is the BMW B38 / B37 reliable?

BMW and MINI's three-cylinder B38 (petrol) and B37 (diesel) have no serious, widespread documented fault. The only problem reported in the press is the crankshaft thrust bearing on early B38 units (up to April 2015), corrected by BMW. BMW's EGR campaigns affect four- and six-cylinder diesels, not the B37.[1][2][3]

See the of the BMW B38 / B37 fault

Is the 1.2 16v reliable?

The 1.2 16v (D4F) and its 8-valve predecessor, the D7F, are simple naturally aspirated engines, used for over two decades as the entry-level option in Renault and Dacia cars, with a reputation for reliability: the reliability pages consulted document no catastrophic failures and no oil consumption. The most-cited problems are ignition coils and sensors and, on higher-mileage cars, the head gasket.[4][5][6][7]

See the 5 of the 1.2 16v faults

Side-by-side comparison

Comparison of BMW B38 / B37 and 1.2 16v
BMW B38 / B371.2 16v
Technical data
TypeEngineEngine
FuelPetrolPetrol
Displacement1,499 cm³1,149 cm³
TimingChainTiming belt (dry)
Power75–231 hp60–76 hp
Productionsince 2014[8][9][10]2001–2020[11][12][13][14]
Reliability
Risk index (what is it?)14Low risk36Moderate risk
Documented faults15
Of high or critical severity11
Worst severityCritical severityHigh severity
Main faults
  1. Critical severity: B38 crankshaft thrust bearing failure (units before April 2015)
  1. High severity: Damaged head gasket and coolant loss
  2. Medium severity: Ignition coil failure (misfires, engine warning light)
  3. Medium severity: Probe and sensor faults (crankshaft position, throttle body)
Most expensive documented repairNo reliable dataNo reliable data
Which versions to buy
BuyRecommended versions
  • B38 1.5 136-140 hp from April 2015 (B38A15 / B38B15)[1]
  • B37 1.5 diesel 95-116 hp (B37C15K0 / B37C15U0), up to 2017[15]
  • B37TÜ1 1.5 diesel 95-116 hp (from late 2017)[16]
With cautionVersions to be cautious about
  • B38 1.2 (B38A12, MINI One)[9]
  • B38 1.5 136 hp up to April 2015 (B38A15)[1]
  • B38K15T0 231 hp (BMW i8)[21]
None
AvoidVersions to avoidNoneNone

Severity of each fault: green, low; amber, medium; red, high; dark red, critical. How we rate them

Cars that each one is fitted to

Other comparisons

With the BMW B38 / B37

With the 1.2 16v

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Sources

Every fact on this page links to its source. If you find an error, let us know.

  1. BMW Dreizylinder: Dauertest-Probleme des B38 behoben?BimmerToday · Motoring press · published 5 October 2017 · consulted 4 October 2026 · in German
  2. 2024: BMW recall due to EGR coolers extended againcar-recalls.eu · Motoring press · published 28 March 2024 · consulted 4 October 2026
  3. BMW diésel Europa: llamada a revisión por el EGR y riesgo de incendioDiariomotor · Motoring press · consulted 4 October 2026 · in Spanish
  4. Fiabilité et pannes de la Renault Clio 2Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  5. Fiabilité et pannes de la Renault Clio 3Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  6. Fiabilité et pannes du Dacia Sandero 2Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  7. Maxi-fiche fiabilité : la Renault Twingo 2Caradisiac · Motoring press · consulted 27 September 2026 · in French
  8. BMW B38 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026
  9. BMW B38 (Wikipedia, alemán)Wikipedia · Other source · consulted 4 October 2026 · in German
  10. BMW B37 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026
  11. Moteur D RenaultWikipédia (francés) · Other source · consulted 27 September 2026 · in French
  12. Anexo:Motores de RenaultWikipedia (español) · Other source · consulted 27 September 2026 · in Spanish
  13. Renault TwingoWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
  14. Renault Clio IIWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
  15. Project one M: MINI Cooper D F56 fährt eine Million Kilometer in 12 JahrenBimmerToday · Motoring press · published 24 June 2026 · consulted 4 October 2026 · in German
  16. BMW Baukasten-Diesel: Mehr Infos zur TÜ1 für B47 und B37BimmerToday · Motoring press · published 20 November 2017 · consulted 4 October 2026 · in German
  17. Fiabilité et pannes de la Renault KangooFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  18. Fiabilité et pannes du Dacia LoganFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  19. Fiabilité et pannes du Dacia SanderoFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  20. Fiabilité et pannes du Dacia Logan 2Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  21. BMW i8 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026