BMW B58 vs 1.5 EcoBoost: which engine is more reliable?

According to our risk index, the BMW B58 carries less risk than the 1.5 EcoBoost: 38/100 versus 43/100 (both moderate risk). The BMW B58 has 1 documented serious fault, the main one being «Failure of the oil pump with a plastic rotor housing»; the 1.5 EcoBoost has 2 documented serious faults, the main one being «Coolant loss through a microcrack in the engine block (4-cylinder 1.5)».

Risk index

BMW B58

Moderate risk · 1 serious fault

Lower risk

Risk index

1.5 EcoBoost

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 30 October 202619 sources How we work

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.^[1][2][3][4]

See the 6 of the BMW B58 faults

Is the 1.5 EcoBoost reliable?

These are two engines with the same name. The four-cylinder (2014-2019: Mondeo, Focus, Kuga, C-Max) has documented cases of coolant loss through a microcrack in the block, which can end in a new engine. The three-cylinder Dragon (from 2018) has hardly any mechanical faults cited, but the Kuga has been recalled several times because an injector can crack and cause a fuel leak with a fire risk.^[5][6][7][8]

See the 2 of the 1.5 EcoBoost faults

Side-by-side comparison

Comparison of BMW B58 and 1.5 EcoBoost
Item	BMW B58	1.5 EcoBoost
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	2,998 cm³	1,498 cm³
Timing	Chain	Chain
Power	290–441 hp	120–200 hp
Production	since 2015^[9][10]	since 2014^{[11][12][13][14][15]}
Reliability
Risk index (what is it?)	38Moderate risk	43Moderate risk
Documented faults	6	2
Of high or critical severity	1	2
Worst severity	High severity	Critical severity
Main faults	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)	Critical severity: Coolant loss through a microcrack in the engine block (4-cylinder 1.5) Critical severity: Fuel leak from cracked injectors, with a fire risk (Kuga Dragon)
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	B58TU2 381 hp (B58B30M2, since 2022)^[2][3]	None
With cautionVersions to be cautious about	B58 326 hp (B58B30M0, 2015-2019)^[2][3][16] B58 340-360 hp (B58B30M0, 2016-2019)^[2][3][16] B58TU 333-340 hp (B58B30M1, since 2018)^[2][3] B58TU 374 hp (B58B30O1, M340i, M440i and M240i, since 2019)^[3]	1.5 EcoBoost 4-cylinder 120/150/160/182 hp (Mondeo, Focus, Kuga, C-Max, S-Max, Galaxy, 2014-2019)^[5][6] 1.5 EcoBoost Dragon 3-cylinder 120/150/182 hp (Kuga III and Focus IV, from 2018)^{[7][8][17][18]} 1.5 EcoBoost ST 200 hp (Fiesta ST 2018-2023 and Puma ST, code YZJA)^[7][13][19]
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 B58

See the 16 models with the BMW B58

1.5 EcoBoost

See the 10 models with the 1.5 EcoBoost

Other comparisons

With the BMW B58

With the 1.5 EcoBoost

Compare other engines

First engine

Second engine

That is the comparison you are viewing: change one of the two engines.

Sources

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

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
Ford Mondeo V - Auto ReviewANWB · Consumer association · published 2 September 2024 · consulted 8 October 2026 · in Dutch
Ford EcoBoost Probleme und Haltbarkeitgebrauchtwagenberater.de · Motoring press · consulted 8 October 2026 · in German
Rückruf: Bei diesen Ford-Modellen besteht BrandgefahrADAC · Motoring press · published 2 February 2026 · consulted 8 October 2026 · in German
Rückruf Ford Kuga: Brandgefahr wegen defekter Einspritzventileauto motor und sport · Motoring press · published 3 May 2024 · consulted 8 October 2026 · in German
BMW B58Wikipedia (inglés) · Other source · consulted 9 October 2026
BMW B58Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
Ford EcoBoost engineWikipedia (en) · Other source · consulted 8 October 2026
Ford EcoBoostWikipedia (de) · Other source · consulted 8 October 2026 · in German
Every Ford Powered By The 1.5L EcoBoost 'Dragon'SlashGear · Motoring press · consulted 8 October 2026
Ford Kuga Titanium 1.5 EcoBoost Auto-Start-Stop 150 CV 4x2 (2014-2016): precio y ficha técnicakm77 · Technical documentation · consulted 8 October 2026 · in Spanish
Ford Kuga MK3 2019-2026 Probleme und Schwachstellengebrauchtwagenberater.de · Motoring press · consulted 8 October 2026 · in German
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
Trois problèmes avec le Ford Kuga : jauge de carburant, injecteurs et toit panoramique défectueuxcar-recalls.eu · Other source · consulted 8 October 2026 · in French
Tous les problèmes sur Ford FOCUS 4 2018 (93 témoignages)fiches-auto.fr · Owners' forum · consulted 8 October 2026 · in French
YZJA engine (Ford 1.5 EcoBoost)Motorinsel · Technical documentation · consulted 8 October 2026