BMW B48 / B38 vs 1.4 Turbo: which engine is more reliable?

According to our risk index, the BMW B48 / B38 carries less risk than the 1.4 Turbo: 24/100 (low risk) versus 45/100 (moderate 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 1.4 Turbo has 2 documented serious faults, the main one being «Early engine failure from a cracked piston».

Risk index

BMW B48 / B38

Low risk · 1 serious fault

Lower risk

Risk index

1.4 Turbo

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 27 September 202616 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 1.4 Turbo reliable?

The Opel/Vauxhall 1.4 Turbo (GM Small Gasoline Engine; A14NET, A14NEL, B14NET and, from 2015-2016, B14NEH/B14XFT/D14XFT) powered much of Opel's petrol range between 2009 and 2018, with outputs from 120 to 152 hp. There is no documented timing chain failure pattern, but there is one for the water pump and thermostat housing, the ignition coils, turbocharger wear and, in fewer cases, early engine failure from a cracked piston.^{[4][5][6][7][8][9]}

See the 4 of the 1.4 Turbo faults

Side-by-side comparison

Comparison of BMW B48 / B38 and 1.4 Turbo
Item	BMW B48 / B38	1.4 Turbo
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	1,998 cm³	1,364 cm³
Timing	Chain	Chain
Power	136–312 hp	120–152 hp
Production	since 2014^[1][10][11]	2009–2018^{[4][12][13][14]}
Reliability
Risk index (what is it?)	24Low risk	45Moderate risk
Documented faults	4	4
Of high or critical severity	1	2
Worst severity	High severity	Critical 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	Critical severity: Early engine failure from a cracked piston High severity: Whistling, loss of power and turbocharger wear Medium severity: Coolant leak from the water pump or thermostat housing
Most expensive documented repair	No reliable data	up to €600Ignition coil failurePublished figure^[6]
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][15] B48 2.0 up to 302-312 hp, high performance (MINI John Cooper Works, BMW X1 M35i)^[2]	None
With cautionVersions to be cautious about	None	1.4 Turbo 120-140 hp (A14NET/A14NEL/B14NET, indirect injection, 2009-2015)^[5][6][7][8] 1.4 Turbo 150-152 hp (B14NEH/B14XFT/D14XFT, from 2015-2016)^[9][16]
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 17 models with the BMW B48 / B38

1.4 Turbo

See the 10 models with the 1.4 Turbo

Other comparisons

With the BMW B48 / B38

With the 1.4 Turbo

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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
Opel Astra JWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel Astra 3 : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Opel Mokka : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Opel Meriva 2 : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Opel Zafira Tourer : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Opel Astra 5 : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
BMW B38Wikipedia (inglés) · Other source · consulted 27 September 2026
BMW B48Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
GM Family 0 engineWikipedia (inglés) · Other source · consulted 27 September 2026
Opel InsigniaWikipedia (español) · Other source · consulted 27 September 2026 · in Spanish
Opel MokkaWikipedia (español) · Other source · consulted 27 September 2026 · in Spanish
5 BMWs That Prove the B48 Four-Cylinder Engine Is Better Than You ThinkBMWBLOG · Other source · published April 2026 · consulted 27 September 2026
Opel Adam : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French