Skip to content
MotorFiable
en

0.9 TwinAir and 1.0/1.3 FireFly vs 1.6 THP: which engine is more reliable?

According to our risk index, the 0.9 TwinAir and 1.0/1.3 FireFly carries less risk than the 1.6 THP: 32/100 (moderate risk) versus 64/100 (high risk). The 0.9 TwinAir and 1.0/1.3 FireFly has 1 documented serious fault, the main one being «Early turbocharger failure (0.9 TwinAir)»; the 1.6 THP has 2 documented serious faults, the main one being «Timing chain and tensioner stretch (turbo versions, before 2012)».

Risk index

0.9 TwinAir and 1.0/1.3 FireFly

32

Moderate risk · 1 serious fault

Lower risk

Risk index

1.6 THP

64

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

15 sourcesHow we work

Is the 0.9 TwinAir and 1.0/1.3 FireFly reliable?

The 0.9 TwinAir (2010-2020) and the 1.0/1.3 FireFly (from 2018, with a mild-hybrid version from 2020) are the small petrol engines of Fiat, Jeep and Lancia. The TwinAir has no systemic faults, but it does have repeated, minority cases of turbo, MultiAir unit, oil consumption and clutch or flywheel wear, consistent with its uneven two-cylinder running. The newer FireFly has so far recorded little more than isolated Start&Stop faults.[1][2][3][4][5]

See the 5 of the 0.9 TwinAir and 1.0/1.3 FireFly 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.[6][7][8][9]

See the 5 of the 1.6 THP faults

Side-by-side comparison

Comparison of 0.9 TwinAir and 1.0/1.3 FireFly and 1.6 THP
0.9 TwinAir and 1.0/1.3 FireFly1.6 THP
Technical data
TypeEngineEngine
FuelPetrolPetrol
Displacement—1,598 cm³
TimingChainChain
Power70–180 hp120–270 hp
Productionsince 2010[10][11]2006–2018[6][12][13]
Reliability
Risk index (what is it?)32Moderate risk64High risk
Documented faults55
Of high or critical severity12
Worst severityHigh severityCritical severity
Main faults
  1. High severity: Early turbocharger failure (0.9 TwinAir)
  2. Medium severity: MultiAir/UniAir hydraulic unit failure (0.9 TwinAir)
  3. Medium severity: Clutch and flywheel wear (0.9 TwinAir)
  1. Critical severity: Timing chain and tensioner stretch (turbo versions, before 2012)
  2. High severity: Fragile water pump and heat exchanger
  3. Medium severity: High-pressure fuel pump (HPFP) failure on the turbo versions
Most expensive documented repairNo reliable dataNo reliable data
Which versions to buy
BuyRecommended versions
  • 1.0 FireFly Hybrid 70 hp (GSE, from 2020)[1][2]
  • 1.0 GSE T3 Turbo 100-120 hp (FireFly, from 2018)[3][14]
None
With cautionVersions to be cautious about
  • 0.9 TwinAir 78-105 hp (2010-2020)[1][2][4][5]
  • 1.3 GSE T4 Turbo 150-180 hp (FireFly, from 2018)[3]
  • 1.6 VTi 120 / 1.6 16v (EP6/EP6C, N12/N16, naturally aspirated)[9]
  • 1.6 THP medium output (EP6DT/EP6DTS/EP6CDT, N14/N18; 140-190 hp)[7][8][15]
  • 1.6 THP high performance (EP6CDXD/EP6FDTR/EP6CDTR, John Cooper Works N14/N18; 200-270 hp)[7][8][9]
AvoidVersions to avoidNoneNone

Severity of each fault: green, low; amber, medium; red, high; dark red, critical. How we rate them

Cars that each one is fitted to

0.9 TwinAir and 1.0/1.3 FireFly

See the 8 models with the 0.9 TwinAir and 1.0/1.3 FireFly

1.6 THP

See the 16 models with the 1.6 THP

Other comparisons

With the 0.9 TwinAir and 1.0/1.3 FireFly

With the 1.6 THP

Compare other engines

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.

  1. Fiabilité et pannes de la Fiat 500 (2007)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  2. Fiabilité et pannes de la Fiat Panda (depuis 2012)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  3. Fiabilité et pannes du Jeep RenegadeFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  4. Fiat 500 (ab 2007) – alle bekannten Probleme & KrankheitenGebrauchtwagenberater.de · Motoring press · published 24 November 2023 · consulted 27 September 2026 · in German
  5. Fiat Panda III (seit 2011) – Probleme & SchwachstellenGebrauchtwagenberater.de · Motoring press · published 21 January 2023 · consulted 27 September 2026 · in German
  6. Prince engineWikipedia (inglés) · Other source · consulted 27 September 2026
  7. Distribution : les moteurs à problèmesFiches-auto.fr · Motoring press · published April 2025 · consulted 27 September 2026 · in French
  8. Moteurs essence qui consomment de l'huileFiches-auto.fr · Motoring press · published April 2024 · consulted 27 September 2026 · in French
  9. Liste des moteurs qui ont des soucis de refroidissementFiches-auto.fr · Motoring press · published April 2025 · consulted 27 September 2026 · in French
  10. Fiat TwinAir engineWikipedia (inglés) · Other source · consulted 27 September 2026
  11. Fiat Global Small EngineWikipedia (inglés) · Other source · consulted 27 September 2026
  12. Peugeot 308Wikipedia (español) · Other source · consulted 27 September 2026 · in Spanish
  13. Peugeot RCZWikipedia (inglés) · Other source · consulted 27 September 2026
  14. Fiabilité et pannes de la Fiat 500XFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
  15. BMW Recalls Fuel Pumps. Mini Does NotMotoringFile · Motoring press · published 27 October 2010 · consulted 27 September 2026