1.6 and 1.8 Ecotec 16v vs 1.6 THP: which engine is more reliable?

According to our risk index, the 1.6 and 1.8 Ecotec 16v carries less risk than the 1.6 THP: 23/100 (low risk) versus 64/100 (high risk). The 1.6 and 1.8 Ecotec 16v has no documented serious faults; the 1.6 THP has 2 documented serious faults, the main one being «Timing chain and tensioner stretch (turbo versions, before 2012)».

Risk index

1.6 and 1.8 Ecotec 16v

Low risk · 0 serious faults

Lower risk

Risk index

1.6 THP

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 202616 sources How we work

Is the 1.6 and 1.8 Ecotec 16v reliable?

The 1.6 and 1.8 16v Ecotec (Z16XER/A16XER, Z18XER/A18XER) that Opel fitted between 2005 and 2015 to the Astra H and J, Zafira B, Vectra C and Insignia A have a reputation as reliable naturally aspirated engines: the sources consulted document no serious faults or failure patterns, only minor problems such as ignition coils and, on the 1.8, leaks from the oil cooler or thermostat.^[1][2][3][4]

See the 3 of the 1.6 and 1.8 Ecotec 16v faults

Is the 1.6 THP reliable?

The 1.6 THP turbo and its naturally aspirated sibling, the 1.6 VTi, make up the Prince family, developed together with BMW and also used by MINI: they do not have a reputation for reliability. Turbo versions built before 2012 carry a known problem of timing chain stretch, and the whole block shares a water pump described as fragile; the turbo versions add oil consumption and high-pressure fuel pump failures.^[5][6][7][8]

See the 5 of the 1.6 THP faults

Side-by-side comparison

Comparison of 1.6 and 1.8 Ecotec 16v and 1.6 THP
Item	1.6 and 1.8 Ecotec 16v	1.6 THP
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	—	1,598 cm³
Timing	Timing belt (dry)	Chain
Power	115–140 hp	120–270 hp
Production	2005–2015^{[9][10][11][12]}	2006–2018^[5][13][14]
Reliability
Risk index (what is it?)	23Low risk	64High risk
Documented faults	3	5
Of high or critical severity	0	2
Worst severity	Medium severity	Critical severity
Main faults	Medium severity: Oil and coolant leak or mixing via the oil cooler (1.8) Medium severity: Coolant loss through the thermostat or water pump Low severity: Ignition coil failures	Critical severity: Timing chain and tensioner stretch (turbo versions, before 2012) High severity: Fragile water pump and heat exchanger Medium severity: High-pressure fuel pump (HPFP) failure on the turbo versions
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	1.6 16V Ecotec 115 hp (Z16XER/A16XER, 2006-2015)^[1][2][3] 1.8 16V Ecotec 140 hp (Z18XER/A18XER, 2005-2014)^[1][4][15]	None
With cautionVersions to be cautious about	None	1.6 VTi 120 / 1.6 16v (EP6/EP6C, N12/N16, naturally aspirated)^[8] 1.6 THP medium output (EP6DT/EP6DTS/EP6CDT, N14/N18; 140-190 hp)^[6][7][16] 1.6 THP high performance (EP6CDXD/EP6FDTR/EP6CDTR, John Cooper Works N14/N18; 200-270 hp)^[6][7][8]
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

1.6 and 1.8 Ecotec 16v

1.6 THP

See the 16 models with the 1.6 THP

Other comparisons

With the 1.6 and 1.8 Ecotec 16v

With the 1.6 THP

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.

Opel Insignia A – Typische Probleme & KrankheitenGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
Fiabilité Opel Astra (H): pannes et témoignagesFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité Opel Zafira 2 (B): pannes et témoignagesFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité Opel Insignia (A): pannes et témoignagesFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Prince engineWikipedia (inglés) · Other source · consulted 27 September 2026
Distribution : les moteurs à problèmesFiches-auto.fr · Motoring press · published April 2025 · consulted 27 September 2026 · in French
Moteurs essence qui consomment de l'huileFiches-auto.fr · Motoring press · published April 2024 · consulted 27 September 2026 · in French
Liste des moteurs qui ont des soucis de refroidissementFiches-auto.fr · Motoring press · published April 2025 · consulted 27 September 2026 · in French
Opel Astra HWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel ZafiraWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel Astra JWikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Opel Astra J – Typische Probleme & SchwachstellenGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
Peugeot 308Wikipedia (español) · Other source · consulted 27 September 2026 · in Spanish
Peugeot RCZWikipedia (inglés) · Other source · consulted 27 September 2026
Opel Vectra C: ProblemeGebrauchtwagenberater.de · Other source · consulted 27 September 2026 · in German
BMW Recalls Fuel Pumps. Mini Does NotMotoringFile · Motoring press · published 27 October 2010 · consulted 27 September 2026