1. What is the PSA EB Engine?
The PSA EB Engine, also known commercially as PureTech, is a family of in-line three-cylinder gasoline engines. It was launched by Groupe PSA (now Stellantis) in 2012 to replace the old 1.1 L and 1.4 L models of the PSA TU Engine. These engines were conceived under the downsizing philosophy to comply with Euro 5 and Euro 6 standards, seeking a balance between performance, efficiency and low emissions.
Due to its technology and innovation, the PureTech engine was acclaimed in its early days, winning the Best Engine of the Year award in the 1 to 1.4-liter category for four consecutive years, from 2015 to 2018. This engine has been incorporated in numerous models from Citroën, Peugeot, DS, Opel, Toyota and, most recently (from 2023, following the merger with FCA), Jeep.
2. Specifications and Technical Evolution (EB0 and EB2)
The EB family is divided into two main displacements:
| Version | Displacement | Injection | Powers (approx.) |
| EB0 | 999 cm³ (1.0 L) | Multipoint | Up to 68 hp |
| EB2 | 1,199 cm³ (1.2 L) | Direct/Multipoint | From 68 hp to 136 hp |
The most powerful versions of the EB2 use direct injection and turbocharging with intercooler, while the naturally aspirated versions use multipoint injection.
Technology and Design: The engine features an in-line three-cylinder configuration, double overhead camshaft (DOHC) and variable valve timing (VTi). To combat the vibrations inherent in three-cylinder engines, a crankshaft with six counterweights or, in some versions, a counter-rotating shaft was implemented. Pressurized aluminum casting was used for the block. In addition, solutions were applied to reduce friction, such as piston pins, sealing rings and tappets with a DLC anti-friction treatment, and a dual-circuit cooling system that cools the cylinder head first.
3. The Critical Design Problem: The Wet Strap
Despite its initial acknowledgments, the PSA EB engine has revealed a critical design flaw centered on the oil-immersed (or “wet”) timing belt. This system was adopted to reduce friction and noise.
The Degradation Mechanism:
Counterintuitively, the main problem is not the oil, but the gasoline leaking into the crankcase through the piston rings that fail to seal properly.
Contamination and Dilution: Gasoline contaminates and dilutes engine oil, reducing its viscosity and decreasing its lubricating capacity and additive package.
2. Attack on the belt: Gasoline, which acts as a chemical solvent, attacks the belt, composed of nitrile. This causes the belt to swell, widen, and begin to rub against the pulley walls.
3. System Clogging: Belt deterioration generates debris, flakes and rubber shavings. This rubber dust, mixed with the diluted oil, becomes sticky and clogs the microfilters and lubrication lines, especially the oil pump filter screen and the turbo filter.
4. Consequences of Failure and Manufacturer’s Response
Clogging of the lubrication system by belt debris leads to serious consequences:
– Loss of Oil Pressure: Hinders circulation and causes a decrease in lubrication pressure.
– Accelerated wear: Lack of lubrication causes increased metal-to-metal contact, damaging bearings, connecting rods and valves.
– Catastrophic Failures: In the worst cases, it can lead to total engine seizure, where moving parts become blocked by excessive friction, requiring replacement or rebuilding. Belt breakage and loss of synchronization can also occur, causing severe internal damage.
Stellantis Measures (Formerly PSA):
1. Recalls: Stellantis has issued multiple recalls (in late 2020 and in 2022) affecting about one million units in Europe (including Peugeot, Citroën, DS and Opel) due to the risk of oil pump damage caused by the wet belt. Because of these problems, the engine has been colloquially nicknamed “Pudretech”.
Reduced Maintenance Interval: The manufacturer has shortened the belt replacement interval from 180,000 km or 10 years to 100,000 km or six years. Some experts suggest even shorter intervals of 75,000 km or, in Latin America, every 50,000 km.
3. Extended Warranty: The group extended the warranty to 10 years or 175,000 km (whichever comes first), retroactively for the first and second generation models affected, as long as maintenance has been performed in authorized workshops.
4. Evolution (Gen3): Stellantis developed a third generation of the engine (EB2 Gen3) that has replaced the wet belt with a timing chain in the most recent versions (especially the micro-hybrid, MHEV 48V).
5. Final summary
The PSA EB (PureTech) engine is a downsizing engine with a well-conceived mechanical base, but whose Achilles heel is its wet-belt timing design. Although Stellantis has implemented reinforced belts and, in newer generations, migrated to chain, owners of affected units (first and second generation) should be extremely diligent about maintenance intervals, use of approved lubricants (such as 0W20), and pay immediate attention to any low oil pressure warning lights.