The Citroen KFY (TU3A) is a 1,124 cc, inline-three petrol engine produced between 1998 and 2005 as part of PSA Peugeot Citroën's TU engine family. It features a single overhead camshaft (SOHC), 6-valve configuration, and multi-point fuel injection (MPFI), delivering 40 kW (55 PS) at 5,600 rpm with 93 Nm of torque at 2,750 rpm. This compact powerplant was engineered for lightweight urban mobility and optimal fuel efficiency in entry-level superminis.
Fitted to models such as the Citroen Saxo and Peugeot 106, the TU3A was designed for economical city driving with minimal maintenance demands. Emissions compliance was achieved through a three-way catalytic converter and closed-loop lambda control, enabling Euro 2 certification for early builds and Euro 3 compliance for post-2001 variants. Its transverse mounting and front-wheel-drive layout made it ideal for PSA’s A-segment platforms.
One documented concern is premature camshaft lobe wear, particularly in vehicles with extended oil change intervals or use of non-specification lubricants. This issue, referenced in PSA Service Information Bulletin SIB-ENG-001-05, is linked to inadequate valvetrain lubrication under sustained high-RPM operation. From 2002, revised camshaft materials and updated oil pump calibration were introduced to improve durability and oil pressure stability.
Production years 1998–2000 meet Euro 2 standards; 2001–2005 models comply with Euro 3 (VCA UK Type Approval #VCA/EMS/3210).
The Citroen KFY (TU3A) is a 1,124 cc inline-three petrol engine developed for lightweight city cars (1998–2005). It uses multi-point fuel injection and a SOHC 6-valve layout to deliver basic yet reliable performance. Engineered to meet Euro 2 and later Euro 3 emissions standards, it prioritizes simplicity, low cost, and ease of maintenance in entry-level applications.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,124 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-3, SOHC, 6-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 75.0 mm × 84.8 mm | |
| Power output | 40 kW (55 PS) @ 5,600 rpm | |
| Torque | 93 Nm @ 2,750 rpm | |
| Fuel system | Multi-point fuel injection (MPFI) | |
| Emissions standard | Euro 2 (pre-2001); Euro 3 (2001–2005) | |
| Compression ratio | 10.2:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Timing belt (SOHC) | |
| Oil type | PSA B71 2005 (SAE 10W-30) | |
| Dry weight | 89 kg |
The naturally aspirated design provides predictable low-RPM performance ideal for city commuting but requires strict adherence to 60,000 km or 4-year timing belt replacement intervals to prevent valve damage. PSA B71 2005 (10W-30) oil is recommended for optimal camshaft and lifter lubrication. The MPFI system is robust but sensitive to poor fuel quality; use of EN 228-compliant petrol is advised. Post-2002 models benefit from improved camshaft metallurgy and revised oil pump calibration, enhancing valvetrain durability. Avoid sustained high-RPM operation without adequate warm-up to reduce lobe wear risk.
Oil Specs: Requires PSA B71 2005 (10W-30) specification (PSA SIB-ENG-001-05). Compatible with ACEA A1/B1.
Emissions: Euro 3 certification applies to 2001–2005 models only (VCA Type Approval #VCA/EMS/3210). Pre-2001 units meet Euro 2.
Power Ratings: Measured under ISO 1585 standards. Output assumes clean air filter, correct ignition timing, and 95 RON fuel (PSA TIS Doc. B11300).
PSA Technical Information System (TIS): Docs B11000, B11250, SIB-ENG-001-05
VCA Type Approval Database (VCA/EMS/3210)
ISO 1585 Road vehicles — Test method for the measurement of fuel consumption
The Citroen KFY (TU3A) was used across Citroen's Saxo platform with transverse mounting and shared with Peugeot under PSA Group commonality agreements. This engine received platform-specific calibrations—slightly tuned throttle response in the Saxo and revised exhaust tuning in the 106—and from 2002 the updated Saxo adopted a redesigned intake manifold and updated ECU mapping, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the right-side engine block near the starter motor (PSA TIS B11000). The 8th VIN digit indicates engine type ('C' for TU3 series). Pre-2002 models use a silver camshaft cover with ribbed intake manifold; post-2002 units feature a black cover with smooth intake casting. Critical differentiation from TU3M: TU3A has MPFI fuel system, while TU3M is carburetted. Service parts require model-year verification—timing belts and cylinder head gaskets for pre-2002 models are not compatible with later revisions due to bolt pattern and sealing changes (PSA SIB-ENG-001-05).
The TU3A's primary reliability risk is camshaft lobe wear, with elevated incidence in vehicles subjected to prolonged high-RPM operation. Internal PSA field reports from 2004 indicated a significant number of pre-2002 units required camshaft replacement before 100,000 km, while UK DVSA data links a portion of emissions-related failures to lambda sensor degradation. Infrequent oil changes and delayed timing belt service increase mechanical stress, making fluid maintenance critical.
Analysis derived from PSA technical bulletins (2000–2005) and UK DVSA failure statistics (2000–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about CITROEN KFY-TU3A.
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