BMW B38 / B37 vs Honda e:HEV / i-MMD: which engine is more reliable?

According to our risk index, the BMW B38 / B37 carries less risk than the Honda e:HEV / i-MMD: 20/100 (low risk) versus 34/100 (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 Honda e:HEV / i-MMD has 2 documented serious faults, the main one being «Cracked high-pressure fuel pump (Honda campaign 6YP)».

Risk index

BMW B38 / B37

Low risk · 1 serious fault

Lower risk

Risk index

Honda e:HEV / i-MMD

Moderate risk · 2 serious faults

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

Reviewed on 30 October 202614 sources How 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 3 of the BMW B38 / B37 faults

Is the Honda e:HEV / i-MMD reliable?

The Honda e:HEV hybrid system (formerly i-MMD) has no serious, widespread faults documented in the sources consulted. The most cited issue is the 12 V battery going flat when the car stands unused and, on the 2.0, a recall for the high-pressure fuel pump.^[4][5][6]

See the 3 of the Honda e:HEV / i-MMD faults

Side-by-side comparison

Comparison of BMW B38 / B37 and Honda e:HEV / i-MMD
Item	BMW B38 / B37	Honda e:HEV / i-MMD
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	1,499 cm³	—
Timing	Chain	Chain
Power	75–231 hp	109–184 hp
Production	since 2014^[7][8][9]	since 2018^[4][10]
Reliability
Risk index (what is it?)	20Low risk	34Moderate risk
Documented faults	3	3
Of high or critical severity	1	2
Worst severity	Critical severity	High severity
Main faults	Critical severity: B38 crankshaft thrust bearing failure (units before April 2015) Medium severity: Coolant leaks and water pump or thermostat failure on the B38 Low severity: Carbon build-up on the B38's intake valves and injectors	High severity: Cracked high-pressure fuel pump (Honda campaign 6YP) High severity: Faulty fuel pump impeller on the 2019-2020 CR-V hybrid (Honda 6FE campaign) Low severity: 12 V battery going flat and hybrid system failing to start
Most expensive documented repair	No reliable data	up to €25012 V battery going flat and hybrid system failing to startPublished figure^[4]
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^[11] B37TÜ1 1.5 diesel 95-116 hp (from late 2017)^[12]	e:HEV 1.5 (LEB-H5) 109-131 hp system output (Jazz IV, HR-V III)^[4][10]
With cautionVersions to be cautious about	B38 1.2 (B38A12, MINI One)^[8] B38 1.5 136 hp up to April 2015 (B38A15)^[1] B38K15T0 231 hp (BMW i8)^[13]	i-MMD 2.0 184 hp system output (CR-V V hybrid)^[4][5] e:HEV 2.0 184 hp system output (Civic XI)^[5][14]
AvoidVersions to avoid	None	None

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

Cars that each one is fitted to

BMW B38 / B37

See the 16 models with the BMW B38 / B37

Honda e:HEV / i-MMD

Other comparisons

With the BMW B38 / B37

With the Honda e:HEV / i-MMD

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Sources

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

BMW Dreizylinder: Dauertest-Probleme des B38 behoben?BimmerToday · Motoring press · published 5 October 2017 · consulted 4 October 2026 · in German
2024: BMW recall due to EGR coolers extended againcar-recalls.eu · Motoring press · published 28 March 2024 · consulted 4 October 2026
BMW diésel Europa: llamada a revisión por el EGR y riesgo de incendioDiariomotor · Motoring press · consulted 4 October 2026 · in Spanish
Sistema híbrido Honda e:HEV (i-MMD): problemas, fiabilidad y coches que lo llevanMotordex · Technical documentation · consulted 29 October 2026 · in Spanish
Honda recalls 1.3 million cars: fuel pump fire risk (KBA 14559R)Car-Recalls.eu · Motoring press · published 17 March 2025 · consulted 29 October 2026
Fiabilité Honda HR-V (2022): pannes et témoignagesFiches-auto.fr · Motoring press · consulted 30 October 2026 · in French
BMW B38 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026
BMW B38 (Wikipedia, alemán)Wikipedia · Other source · consulted 4 October 2026 · in German
BMW B37 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026
Honda LEB-H5 (1.5 i-MMD e:HEV): experiencias, problemas, consumo y consejos de compraAutohints · Technical documentation · consulted 29 October 2026 · in Spanish
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
BMW Baukasten-Diesel: Mehr Infos zur TÜ1 für B47 und B37BimmerToday · Motoring press · published 20 November 2017 · consulted 4 October 2026 · in German
BMW i8 (Wikipedia)Wikipedia · Other source · consulted 4 October 2026
Guide d'achat Honda Civic (nueva campaña 6YP, 4.740 híbridos en Francia)L'argus · Motoring press · published 7 January 2025 · consulted 29 October 2026 · in French