1.0 and 1.4 Boosterjet vs 1.2 12V: which engine is more reliable?

According to our risk index, the 1.0 and 1.4 Boosterjet carries less risk than the 1.2 12V: 6/100 (low risk) versus 57/100 (high risk). The 1.0 and 1.4 Boosterjet has no documented serious faults; the 1.2 12V has 2 documented serious faults, the main one being «Timing chain stretch and tensioner wear».

Risk index

1.0 and 1.4 Boosterjet

Low risk · 0 serious faults

Lower risk

Risk index

1.2 12V

High 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 202620 sources How we work

Is the 1.0 and 1.4 Boosterjet reliable?

The Suzuki Boosterjet (1.0 K10C and 1.4 K14C/K14D) is a turbocharged direct-injection petrol engine with a timing chain, fitted since 2015 to the Vitara, S-Cross, Swift Sport and Baleno, with a 48 V mild-hybrid variant of the 1.4 since 2020. German TÜV inspection reports and the workshops we consulted rate its reliability as high: no widespread fault with the chain, oil, fuel pump or mild-hybrid system is documented.^{[1][2][3][4][5]}

See the 4 of the 1.0 and 1.4 Boosterjet faults

Is the 1.2 12V reliable?

The 1.2 12V is a simple, low-power, naturally aspirated three-cylinder engine (54-70 hp), with two documented design faults: the timing chain tensioner, which can end up destroying the engine, and -on the Volkswagen Polo IV- a catalytic converter too close to the cylinder head that can burn the exhaust valves. Ignition coil failures are also common, and there are isolated cases of oil consumption and vibration.^{[6][7][8][9][10]}

See the 5 of the 1.2 12V faults

Side-by-side comparison

Comparison of 1.0 and 1.4 Boosterjet and 1.2 12V
Item	1.0 and 1.4 Boosterjet	1.2 12V
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	—	1,198 cm³
Timing	Chain	Chain
Power	110–140 hp	54–70 hp
Production	since 2015^{[1][11][12][13]}	2001–2014^[6][14][15]
Reliability
Risk index (what is it?)	6Low risk	57High risk
Documented faults	4	5
Of high or critical severity	0	2
Worst severity	Low severity	Critical severity
Main faults	Low severity: Timing chain: no documented pattern of failures Low severity: Oil consumption: no documented pattern Low severity: Direct injection and fuel pump: no documented faults or recalls	Critical severity: Timing chain stretch and tensioner wear High severity: Cylinder head and valve damage from exhaust gas backflow (Volkswagen Polo IV) Medium severity: Higher-than-normal oil consumption
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	1.0 Boosterjet 110-112 hp (K10C, three-cylinder, 2015-present)^{[2][3][16][17]} 1.4 Boosterjet 140 hp (K14C, non-hybrid, 2015-2020 in Europe)^[2][3][18] 1.4 Boosterjet Mild Hybrid 129 hp (K14D, 48V SHVS, since 2020)^[12][13]	None
With cautionVersions to be cautious about	None	1.2 54/60 hp (AWY, BMD, BBM, 2001-2014)^[6][8] 1.2 64/70 hp (BME, CGPA, 2002-2014)^{[6][8][19][20]}
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

1.0 and 1.4 Boosterjet

See the 12 models with the 1.0 and 1.4 Boosterjet

1.2 12V

See the 7 models with the 1.2 12V

Other comparisons

With the 1.0 and 1.4 Boosterjet

With the 1.2 12V

Compare other engines

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Sources

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

Suzuki K engineWikipedia · Other source · consulted 27 September 2026
Gebrauchtwagen-Check: Grundsätzlich gut: Der Suzuki Vitara beim TÜVVolksstimme (dpa) · General press · published January 2026 · consulted 27 September 2026 · in German
Suzuki Swift als Gebrauchtwagen: Diese Punkte beanstandet der TÜV häufigT-Online · General press · published October 2025 · consulted 27 September 2026 · in German
Los mecánicos recomiendan el Suzuki Vitara porque no presume de moderno, sino de sencillo y baratoEl Nacional · General press · published September 2026 · consulted 27 September 2026 · in Spanish
Test complet Suzuki VitaraFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
VW Polo 4 (9N): Typische Probleme & SchwachstellenGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
Fiabilité et pannes de la Volkswagen Polo 4Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes de la Seat Ibiza (2008-2017)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Seat Ibiza III (2002-2008): Bekannte Probleme & KrankheitenGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
Fiabilité et pannes de la Seat Ibiza (2002-2008)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Suzuki motor KWikipedia · Other source · consulted 27 September 2026 · in Spanish
Suzuki Swift Sport, Vitara y S-Cross: nuevas versiones micro-híbridas de 48VAutopista.es · Motoring press · published 16 December 2019 · consulted 27 September 2026 · in Spanish
Suzuki S-Cross 1.4 Boosterjet Mild Hybrid 2020: precios y datos del nuevo SUVAutopista.es · Motoring press · published 12 March 2020 · consulted 27 September 2026 · in Spanish
VW EA111Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
VW Polo IVWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Suzuki Vitara : avis, qualités et défauts des propriétairesFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Suzuki Swift 3 : avis, qualités et défauts des propriétairesFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Prueba Suzuki Swift Sport 1.4 Boosterjet 140 CVActualidad Motor · Motoring press · published 16 May 2018 · consulted 27 September 2026 · in Spanish
Fiabilité et pannes de la Volkswagen Polo 5Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes de la Skoda Fabia 2Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French