BMW B48 / B38 vs 1.2 Dualjet and 1.2 VVT: which engine is more reliable?

According to our risk index, the 1.2 Dualjet and 1.2 VVT carries less risk than the BMW B48 / B38: 23/100 versus 24/100 (both low risk). The BMW B48 / B38 has 1 documented serious fault, the main one being «Timing chain on the early units (2014-2018), redesigned in the B48TU»; the 1.2 Dualjet and 1.2 VVT has no documented serious faults.

Risk index

BMW B48 / B38

Low risk · 1 serious fault

Risk index

1.2 Dualjet and 1.2 VVT

Low risk · 0 serious faults

Lower risk

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

Reviewed on 27 September 202613 sources How we work

Is the BMW B48 / B38 reliable?

The BMW B48 (2.0 turbo, from 2014) and its three-cylinder sibling, the B38 (1.5), have a reputation as reliable engines within BMW's modern range: there is no serious, widespread fault on record, unlike the timing chain on the N47 diesel or the EGR fire risk on the B47. Keep an eye on the cooling circuit, the oil seals near the turbo and the VANOS, and the carbon build-up typical of direct injection; BMW revised the timing chain in 2018 (B48TU update).^[1][2][3]

See the 4 of the BMW B48 / B38 faults

Is the 1.2 Dualjet and 1.2 VVT reliable?

The Suzuki 1.2 VVT and 1.2 Dualjet (K12B/K12C/K12M) is a naturally aspirated petrol engine with a timing chain and indirect injection, fitted since 2008 to the Splash, Swift, Ignis and Baleno, with an SHVS mild-hybrid variant since 2016. It is reliable: there is no serious documented fault with the engine block itself; the main points are a clutch that wears out sooner than expected on some cars and two SHVS recalls that have already been resolved.^{[4][5][6][7][8]}

See the 5 of the 1.2 Dualjet and 1.2 VVT faults

Side-by-side comparison

Comparison of BMW B48 / B38 and 1.2 Dualjet and 1.2 VVT
Item	BMW B48 / B38	1.2 Dualjet and 1.2 VVT
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	1,998 cm³	—
Timing	Chain	Chain
Power	136–312 hp	82–92 hp
Production	since 2014^[1][9][10]	since 2008^[4][5]
Reliability
Risk index (what is it?)	24Low risk	23Low risk
Documented faults	4	5
Of high or critical severity	1	0
Worst severity	High severity	Medium severity
Main faults	Medium severity: Deterioration of hoses and seals in the cooling circuit, with coolant loss Medium severity: Oil leaks or seepage from seals and covers, near the turbo and the VANOS High severity: Timing chain on the early units (2014-2018), redesigned in the B48TU	Medium severity: Clutch: premature wear and clutch cable anchor failure Medium severity: SHVS mild-hybrid system: recalls for the starter generator belt and software Medium severity: Water pump pulley fixing (2013-2014): recall
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	B38 1.5 136 hp (MINI Cooper, 118i)^[2] B48 2.0 178-197 hp (120i, 220i, 320i, 520i, X1/X2/X3 20i, MINI Cooper S)^[2] B48 2.0 252-258 hp (330i, 530i, X3/X4 xDrive30i)^[2][11] B48 2.0 up to 302-312 hp, high performance (MINI John Cooper Works, BMW X1 M35i)^[2]	1.2 VVT 86-92 hp (K12B, one injector per cylinder, 2008-2013)^[7] 1.2 Dualjet non-hybrid 89-91 hp (K12B/K12C, dual injector, 2013-2020)^[8][12][13] 1.2 Dualjet SHVS mild hybrid 82-90 hp (K12C/K12D, since 2016)^[8]
With cautionVersions to be cautious about	None	None
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 B48 / B38

See the 20 models with the BMW B48 / B38

1.2 Dualjet and 1.2 VVT

See the 7 models with the 1.2 Dualjet and 1.2 VVT

Other comparisons

With the BMW B48 / B38

With the 1.2 Dualjet and 1.2 VVT

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Sources

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

BMW B48Wikipedia (inglés) · Other source · consulted 27 September 2026
Motor BMW B48: defectos, mantenimiento y guía de compraRecambios y Accesorios BMW (blog) · Technical documentation · consulted 27 September 2026 · in Spanish
BMW Reliability Has Changed, But the Internet Hasn't Caught UpBMWBLOG · Other source · published January 2026 · consulted 27 September 2026
Suzuki motor KWikipedia · Other source · consulted 27 September 2026 · in Spanish
Suzuki K engineWikipedia · Other source · consulted 27 September 2026
Suzuki Swift (NZ) – Typische Probleme & SchwachstellenGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
Suzuki Splash (2008–2014) – Bekannte Probleme & KrankheitenGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
Suzuki Ignis (MF, ab 2016) – Bekannte Probleme & SchwachstellenGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
BMW B38Wikipedia (inglés) · Other source · consulted 27 September 2026
BMW B48Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
5 BMWs That Prove the B48 Four-Cylinder Engine Is Better Than You ThinkBMWBLOG · Other source · published April 2026 · consulted 27 September 2026
Suzuki Ignis : avis, qualités et défauts des propriétairesFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Suzuki Swift 2 : avis, qualités et défauts des propriétairesFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French