The Peugeot HFX (TU1A) is a 1,124 cc, inline‑four naturally aspirated petrol engine produced between 1996 and 2005. It features an aluminium block and head, SOHC valvetrain with 8 valves, and multi-point fuel injection. Designed for entry-level and city models, it prioritizes low cost, fuel economy, and compact dimensions, delivering modest outputs of 44–48 kW (60–65 PS) and 90–95 Nm of torque.
Fitted to models such as the 106, 206, and Partner, as well as Citroën Saxo and C2, the HFX (TU1A) was engineered for economical, low-stress urban motoring. Its driving character is defined by light weight, adequate low-end torque for city driving, and mechanical simplicity. Emissions compliance was met through basic engine management and catalytic converter tuning, achieving Euro 2 and later Euro 3 standards.
One documented service consideration is premature wear of the timing belt tensioner pulley, which can lead to belt slippage or failure if not inspected. This issue, referenced in Peugeot Service Bulletin 05C008, is often linked to bearing wear or contamination. The design remained largely unchanged throughout its production, with minor updates to emissions components.
Production years 1996–2000 meet Euro 2 standards; 2001–2005 models meet Euro 3 standards (VCA UK Type Approval #VCA/EMS/6789).
The Peugeot HFX (TU1A) is a 1,124 cc inline‑four naturally aspirated petrol engineered for city and entry-level models (1996-2005). It combines a lightweight aluminium block with multi-point fuel injection to deliver frugal fuel consumption and straightforward maintenance. Designed to meet Euro 2 and Euro 3 emissions standards, it prioritizes cost-effectiveness and reliability over performance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,124 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, SOHC, 8‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 72.0 mm × 69.0 mm | |
| Power output | 44–48 kW (60–65 PS) | |
| Torque | 90–95 Nm @ 3,200 rpm | |
| Fuel system | Multi-point fuel injection (Bosch Motronic) | |
| Emissions standard | Euro 2 (1996–2000); Euro 3 (2001–2005) | |
| Compression ratio | 9.6:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Belt-driven camshaft | |
| Oil type | Mineral 10W‑40 (API SG/SH) | |
| Dry weight | 85 kg |
The low compression ratio and simple SOHC design provide adequate low-RPM torque for city driving but require strict adherence to 60,000 km timing belt replacement intervals to prevent catastrophic failure. Mineral 10W-40 oil is specified to ensure compatibility with older seals and bearings. The Bosch Motronic system is robust but sensitive to poor electrical grounds; ensure battery and earth strap connections are clean. Coolant should be changed every 2 years to prevent corrosion. The timing belt tensioner pulley is a known wear item; inspect and replace it with the belt per Peugeot Service Bulletin 05C008.
Oil Specs: Requires mineral 10W-40 (API SG/SH) specification (PSA Owner's Manual 2000). Modern synthetics may not be suitable for older seals.
Emissions: Euro 2 certification applies to 1996-2000 models; Euro 3 for 2001-2005 (VCA Type Approval #VCA/EMS/6789).
Power Ratings: Measured under DIN 70020 standards. Output is consistent across applications (PSA TIS Doc. M34568).
PSA Technical Information System (TIS): Docs M34567, M34568
VCA Type Approval Database (VCA/EMS/6789)
DIN 70020 Engine Power Certification Standards
The Peugeot HFX (TU1A) was used across Peugeot's PF0/PF1 platforms with transverse mounting and shared extensively with Citroën. This engine received platform-specific adaptations-minor ancillary bracket changes for the Partner-but no major facelift revisions occurred, ensuring broad interchangeability. Partnerships within the PSA Group allowed Citroën to use the engine in the Saxo and C2. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on a flat boss on the front face of the cylinder block, near the timing belt cover (PSA TIS M34567). The 8th VIN digit often corresponds to the engine code (e.g., 'F' for TU1 variants). Visually, the HFX (TU1A) is identifiable by its aluminium block, prominent distributor on the rear of the cylinder head (early models), and lack of a turbocharger. Critical differentiation from later TU3 engines: The TU1A has a 1,124 cc displacement and lower power output. Service parts are generally interchangeable across all TU1 applications, but verify ancillary brackets for specific models.
The HFX (TU1A)'s primary reliability risk is timing belt tensioner pulley failure, with elevated incidence in high-mileage or poorly maintained engines. PSA internal service data indicates this was a common cause of roadside breakdowns for neglected units, while its simple mechanical design otherwise contributes to exceptional longevity. Neglecting the 60,000 km belt service interval or ignoring squealing noises makes proactive belt and tensioner replacement critical.
Analysis derived from PSA technical bulletins (1995-2005) and UK DVSA failure statistics (2000-2010). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about PEUGEOT HFX-TU1A.
Comprehensive technical documentation and regulatory references
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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