1.0 EcoBoost vs BMW B58: which engine is more reliable?

According to our risk index, the BMW B58 carries less risk than the 1.0 EcoBoost: 38/100 (moderate risk) versus 71/100 (high risk). The 1.0 EcoBoost has 3 documented serious faults, the main one being «Degradation of the timing belt running in oil»; the BMW B58 has 1 documented serious fault, the main one being «Failure of the oil pump with a plastic rotor housing».

Risk index

1.0 EcoBoost

High risk · 3 serious faults

Risk index

BMW B58

Moderate risk · 1 serious fault

Lower risk

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

Reviewed on 9 October 202618 sources How we work

Is the 1.0 EcoBoost reliable?

It is a turbocharged direct-injection three-cylinder that has won Engine of the Year several times, but it has two very well-documented weak points: two belts running in oil (timing and oil pump) that can disintegrate and seize the engine, and cases of coolant leaks and overheating in early units. It is best bought with a service history and the belts checked or replaced on time.^[1][2][3][4]

See the 4 of the 1.0 EcoBoost faults

Is the BMW B58 reliable?

The B58 (3.0 turbo straight-six, since 2015) is considered robust and less troublesome than the N54/N55 it replaced, and the sources do not document widespread internal failures. The known faults are on the periphery: the plastic oil filter housing, crankcase ventilation, gaskets and coolant. On units built before 2021 there are also US reports of an oil pump with a plastic housing.^[5][6][7][8]

See the 6 of the BMW B58 faults

Side-by-side comparison

Comparison of 1.0 EcoBoost and BMW B58
Item	1.0 EcoBoost	BMW B58
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	999 cm³	2,998 cm³
Timing	Wet belt (belt-in-oil)	Chain
Power	100–155 hp	290–441 hp
Production	since 2012^{[1][9][10][11]}	since 2015^[12][13]
Reliability
Risk index (what is it?)	71High risk	38Moderate risk
Documented faults	4	6
Of high or critical severity	3	1
Worst severity	Critical severity	High severity
Main faults	Critical severity: Degradation of the timing belt running in oil Critical severity: Oil pump belt and tensioner failure Critical severity: Coolant leaks and overheating from the turbo hose	High severity: Failure of the oil pump with a plastic rotor housing Medium severity: Oil and coolant leak from the plastic oil filter housing Medium severity: Failure of the crankcase ventilation PCV valve (integrated in the valve cover)
Most expensive documented repair	up to €1,200Degradation of the timing belt running in oilPublished figure^[2]	No reliable data
Which versions to buy
BuyRecommended versions	None	B58TU2 381 hp (B58B30M2, since 2022)^[6][7]
With cautionVersions to be cautious about	1.0 EcoBoost 100/125 (Fox, 2012-2017)^[2][3][14] 1.0 EcoBoost 100/125/140 with cylinder deactivation (from ~2017)^[15][16] 1.0 EcoBoost Hybrid 48V mild hybrid (125/155 hp, from 2019)^[1][17]	B58 326 hp (B58B30M0, 2015-2019)^[6][7][18] B58 340-360 hp (B58B30M0, 2016-2019)^[6][7][18] B58TU 333-340 hp (B58B30M1, since 2018)^[6][7] B58TU 374 hp (B58B30O1, M340i, M440i and M240i, since 2019)^[7]
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 EcoBoost

See the 11 models with the 1.0 EcoBoost

BMW B58

See the 15 models with the BMW B58

Other comparisons

With the 1.0 EcoBoost

With the BMW B58

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.

Ford EcoBoost engineWikipedia · Other source · consulted 26 September 2026
Alerta Ford: la correa de distribución del 1.0 EcoBoost puede romper el motor y la NHTSA ya investigaMotor16 · Motoring press · consulted 26 September 2026 · in Spanish
Los Ford 1.0 EcoBoost tricilíndricos están dando problemas de correas bañadas que recuerdan al caso PureTechMotor.es · Motoring press · consulted 26 September 2026 · in Spanish
Gripa el motor por problema en el manguito se queda sin refrigeranteOpinautos · Owners' forum · consulted 26 September 2026 · in Spanish
The 5 Most Common BMW B58 Engine ProblemsBMW Tuning · Technical documentation · published 7 February 2020 · consulted 9 October 2026
BMW B58 EngineFCP Euro · Technical documentation · consulted 9 October 2026
The Popular BMW B58 Inline-Six Engine Has One Big Achilles HeelThe Autopian · Motoring press · published 14 June 2024 · consulted 9 October 2026
¿En qué se diferencian los motores B58 y S58 de BMW?Diariomotor · Motoring press · published 27 April 2024 · consulted 9 October 2026 · in Spanish
Prueba: Ford Fiesta 1.0 EcoBoost 100 CV (2013)km77 · Motoring press · consulted 26 September 2026 · in Spanish
Ford Mondeo Berlina Trend 1.0 EcoBoost 92 kW (125 CV) (2015-2018): precio y ficha técnicakm77 · Technical documentation · consulted 26 September 2026 · in Spanish
Ford B-MAX Trend 1.0 EcoBoost 100 CV (2012-2018): precio y ficha técnicakm77 · Technical documentation · consulted 26 September 2026 · in Spanish
BMW B58Wikipedia (inglés) · Other source · consulted 9 October 2026
BMW B58Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
Ford EcoBoost engines: reliability, problems and should you buy one?Carbuyer · Motoring press · consulted 26 September 2026
Ford's Self-Clogging 1.0-Liter EcoBoost Engine Is Finally Getting RecalledThe Drive · Motoring press · consulted 26 September 2026
The Largest Ford EcoBoost Recalls In 15 Years Of ProductionCarBuzz · Motoring press · consulted 26 September 2026
Stellantis no es el único afectado por la correa de distribución bañada en aceiteAutofácil · Motoring press · consulted 26 September 2026 · in Spanish
How A Plastic Part On BMW's B58 Engine Can Turn An Oil Change Into A $3,000 RepairThe Autopian · Motoring press · published 28 March 2025 · consulted 9 October 2026