BMW B48 / B38 vs 1.2 8v Fire: which engine is more reliable?

According to our risk index, the 1.2 8v Fire carries less risk than the BMW B48 / B38: 20/100 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 8v Fire has no documented serious faults.

Risk index

BMW B48 / B38

Low risk · 1 serious fault

Risk index

1.2 8v Fire

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 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 1.2 8v Fire reliable?

The 1.2 8v Fire is one of Fiat's simplest and most widespread petrol engines, with more than two decades in production and no serious or systemic faults documented. The sources consulted describe it as robust: its most-cited issues are isolated sensor failures (lambda sensor, crankshaft sensor), the ignition coil and somewhat high oil consumption at higher mileages; there is no pattern of timing belt breakage.^{[4][5][6][7][8][9]}

See the 4 of the 1.2 8v Fire faults

Side-by-side comparison

Comparison of BMW B48 / B38 and 1.2 8v Fire
Item	BMW B48 / B38	1.2 8v Fire
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	1,998 cm³	1,242 cm³
Timing	Chain	Timing belt (dry)
Power	136–312 hp	60–69 hp
Production	since 2014^[1][10][11]	1999–2020^{[12][13][14][15]}
Reliability
Risk index (what is it?)	24Low risk	20Low risk
Documented faults	4	4
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: Sensor failures: lambda sensor and crankshaft position sensor (TDC) Low severity: Oil consumption or leak, in one case from the rocker cover gasket Low severity: Faulty ignition coil (misfire, engine warning light)
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][16] B48 2.0 up to 302-312 hp, high performance (MINI John Cooper Works, BMW X1 M35i)^[2]	1.2 8v SMPI 60-65 hp (1999-2009)^[4] 1.2 8v VVT 69 hp (2007-2020)^[5][6][8][9]
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 17 models with the BMW B48 / B38

1.2 8v Fire

See the 7 models with the 1.2 8v Fire

Other comparisons

With the BMW B48 / B38

With the 1.2 8v Fire

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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
Fiabilité et pannes de la Fiat Panda (2003-2012)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes de la Fiat Panda (depuis 2012)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes de la Fiat 500Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes de la Fiat Punto (Grande Punto / Punto Evo / Punto)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiat Panda III (seit 2011) – Probleme & SchwachstellenGebrauchtwagenberater.de · Motoring press · published 21 January 2023 · consulted 27 September 2026 · in German
Fiat 500 (ab 2007) – alle bekannten Probleme & KrankheitenGebrauchtwagenberater.de · Motoring press · published 24 November 2023 · 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
Fiat FIRE engineWikipedia (inglés) · Other source · consulted 27 September 2026
Fiat 500 (2007)Wikipedia (inglés) · Other source · consulted 27 September 2026
Fiat Grande PuntoWikipedia (inglés) · Other source · consulted 27 September 2026
Ford KaWikipedia (inglés) · Other source · consulted 27 September 2026
5 BMWs That Prove the B48 Four-Cylinder Engine Is Better Than You ThinkBMWBLOG · Other source · published April 2026 · consulted 27 September 2026