BMW N57 vs 1.7 CDTI: which engine is more reliable?

According to our risk index, the 1.7 CDTI carries less risk than the BMW N57: 36/100 (moderate risk) versus 87/100 (very high risk). The BMW N57 has 3 documented serious faults, the main one being «EGR cooler leaks with risk of engine fire»; the 1.7 CDTI has 3 documented serious faults, the main one being «Dual-mass flywheel and clutch wear».

Risk index

BMW N57

Very high risk · 3 serious faults

Risk index

1.7 CDTI

Moderate risk · 3 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 202615 sources How we work

Is the BMW N57 reliable?

The BMW N57 (2008-2019, successor to the M57) is a six-cylinder diesel that is mechanically robust in the basics, but it shares with the N47 and B47 the EGR cooler covered by BMW's service campaign for engine fire risk, and it inherits from the N47 the timing chain at the rear of the block, with wear cases documented mainly from 200,000 km. Without a clear history of these checks, it is worth buying with some caution.^[1][2][3]

See the 4 of the BMW N57 faults

Is the 1.7 CDTI reliable?

The 1.7 CDTI (Isuzu, 2003-2015) is a simple, widely used diesel, but it has built up accounts of soot-fouled EGR valves and injectors, a clogged diesel particulate filter (DPF) with oil dilution, wear of the dual-mass flywheel and clutch, and of the Hitachi-brand alternator; it also requires the timing belt to be changed every 150,000 km or 6 years to avoid a serious failure.^{[4][5][6][7][8][9][10]}

See the 5 of the 1.7 CDTI faults

Side-by-side comparison

Comparison of BMW N57 and 1.7 CDTI
Item	BMW N57	1.7 CDTI
Technical data
Type	Engine	Engine
Fuel	Diesel	Diesel
Displacement	2,993 cm³	1,686 cm³
Timing	Chain	Timing belt (dry)
Power	204–381 hp	100–130 hp
Production	2008–2019^[1][11]	2003–2015^[4][12][13]
Reliability
Risk index (what is it?)	87Very high risk	36Moderate risk
Documented faults	4	5
Of high or critical severity	3	3
Worst severity	Critical severity	Critical severity
Main faults	Critical severity: EGR cooler leaks with risk of engine fire Critical severity: Rear timing chain wear High severity: Loss of thrust on twin-turbo versions due to the vacuum circuit or the actuator	High severity: Dual-mass flywheel and clutch wear High severity: Clogged diesel particulate filter (DPF) and oil dilution Critical severity: Timing belt: risk of serious failure if not changed on time
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	None	None
With cautionVersions to be cautious about	N57D30 204-211 hp, single turbo (U0/UL, 2010-2013)^[3][14] N57D30 245-258 hp, single turbo (O0/O1, 2008-2019)^[3][14] N57D30 299-313 hp twin turbo (T0/T1, 2009-2019)^[14][15]	1.7 CDTI 100-101 hp (Z17DTH, 2003-2007)^[9][10] 1.7 CDTI 110 hp (Z17DTJ/A17DTJ/A17DTC/A17DTE, 2007-2014)^[9][10] 1.7 CDTI 125 hp (Z17DTR/A17DTR, 2006-2013)^[5][6] 1.7 CDTI 130 hp (A17DTS, 2010-2015)^[9][10]
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 N57

See the 10 models with the BMW N57

1.7 CDTI

See the 7 models with the 1.7 CDTI

Other comparisons

With the BMW N57

With the 1.7 CDTI

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.

BMW N57Wikipedia (inglés) · Other source · consulted 27 September 2026
Motor BMW B47 - Reparación EspecializadaDasercars · Technical documentation · consulted 27 September 2026 · in Spanish
324.000 diésel de BMW tendrán que pasar por el taller en Europa, por un posible riesgo de incendio en la EGRDiariomotor · Motoring press · published 8 August 2018 · consulted 27 September 2026 · in Spanish
Circle L engineWikipedia (inglés) · Other source · consulted 27 September 2026
Essai complet Opel Astra (H) : fiabilité et avisFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Essai complet Opel Zafira 2 : fiabilité et avisFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Essai complet Opel Meriva : fiabilité et avisFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Opel Astra H (A04): Probleme & KaufberatungGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
Opel Meriva A: ProblemeGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
Opel Meriva B: ProblemeGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
BMW N57Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel Corsa DWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel MerivaWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Motor BMW N57 - Reparación EspecializadaDasercars · Technical documentation · consulted 27 September 2026 · in Spanish
Motor BMW N57: problemas, modelos y qué revisarCarexam · Motoring press · consulted 27 September 2026 · in Spanish