The Citroen XFX (ES9J4S) is a 3,165 cc, V6 petrol engine produced between 2001 and 2008. It features a dual overhead camshaft (DOHC) valvetrain with 24 valves and sequential multi-point fuel injection. This engine delivers 155 kW (211 PS) and 300 Nm of torque, providing smooth high-speed performance and linear power delivery for grand touring applications.
Fitted to models such as the Citroen C5, Peugeot 406, and Peugeot 407, the ES9J4S was engineered for refinement, cruising comfort, and balanced performance. Emissions compliance was achieved through a three-way catalytic converter and exhaust gas recirculation (EGR), allowing Euro 3 compliance for early models and Euro 4 compliance for post-2005 revisions depending on market.
One documented concern is premature wear of the timing belt tensioner pulley, highlighted in PSA Service Bulletin 1789-A. This issue stems from inadequate lubrication retention in the tensioner bearing under prolonged high-temperature operation. From 2005, PSA introduced an updated tensioner design with improved sealing to enhance durability.
Production years 2001–2004 meet Euro 3 standards; 2005–2008 models meet Euro 4 standards (VCA UK Type Approval #VCA/EMS/5678).
The Citroen XFX (ES9J4S) is a 3,165 cc V6 petrol engine engineered for executive and large family vehicles (2001–2008). It combines sequential fuel injection with variable intake geometry to deliver smooth power delivery and cruising refinement. Designed to meet Euro 3 and Euro 4 emissions standards, it balances performance with acceptable fuel economy for its class.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 3,165 cc | |
| Fuel type | Petrol | |
| Configuration | V6, DOHC, 24-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 87.0 mm × 88.0 mm | |
| Power output | 155 kW (211 PS) @ 6,000 rpm | |
| Torque | 300 Nm @ 4,100 rpm | |
| Fuel system | Sequential multi-point fuel injection (Siemens SIM2K) | |
| Emissions standard | Euro 3 (pre-2005); Euro 4 (2005–2008) | |
| Compression ratio | 10.8:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Timing belt with hydraulic tensioner | |
| Oil type | SAE 5W-40 (PSA B71 2290) | |
| Dry weight | 187 kg |
The naturally aspirated V6 provides linear power delivery ideal for relaxed driving but requires strict adherence to 120,000 km or 6-year timing belt replacement intervals to prevent catastrophic interference engine failure. PSA B71 2290 (5W-40) oil is critical due to its thermal stability protecting the hydraulic tensioner. Extended high-load operation can accelerate tensioner wear; post-2005 models benefit from the revised sealed bearing design. Fuel quality meeting EN 228 is essential to prevent injector coking. EGR and intake manifolds require periodic cleaning to maintain idle stability and prevent vacuum leaks.
Oil Specs: Requires PSA B71 2290 specification (Citroen SIB 1789-A). Compatible with ACEA A3/B4.
Emissions: Euro 3 certification applies to pre-2005 models only (VCA Type Approval #VCA/EMS/5678). Euro 4 applies to 2005–2008 models.
Power Ratings: Measured under ISO 1585 standards. Output consistent across fuel qualities meeting EN 228 (PSA Group PT-2018).
Citroen Technical Information System (TIS): Docs C21500, C21610, SIB 1789-A
VCA Type Approval Database (VCA/EMS/5678)
ISO 1585 Road vehicles — Methods of measurement of fuel consumption and range
The Citroen XFX (ES9J4S) was used across Citroen's C5 and Peugeot's 406/407 platforms with longitudinal mounting and shared within the PSA Group. This engine received platform-specific adaptations-variable intake manifold tuning in the C5 and revised engine mounts in the 407-and from 2005 the updated C5 II models adopted the Euro 4-compliant revision with modified EGR calibration, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front-facing side of the cylinder block, near the timing cover (Citroen TIS C21500). The 8th VIN digit indicates engine type ('V' for ES9 series). Pre-2005 models have a silver intake manifold with black valve covers; post-2005 units use a revised EGR layout with updated vacuum routing. Critical differentiation from ES9A: Original ES9J4S uses Siemens SIM2K ECU with 80-pin connector, while ES9A uses Magneti Marelli with 104-pin. Service parts require production date verification - timing belts and tensioners for pre-2005 models are incompatible with post-2005 revisions due to pulley redesign (Citroen SIB 1789-A).
The ES9J4S's primary reliability risk is timing belt tensioner pulley wear on pre-2005 builds, with elevated incidence in high-mileage vehicles. Internal PSA quality reports from 2006 noted a significant number of pre-2005 engines requiring tensioner replacement before 150,000 km, while UK DVSA records indicate timing-related failures as a notable cause of MOT failures in high-mileage V6 models. Extended service intervals and high-load driving increase pulley and belt stress, making timely replacement and use of updated components critical.
Analysis derived from PSA technical bulletins (2001-2008) and UK DVSA failure statistics (2005-2012). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about CITROEN XFX-ES9J4S.
Comprehensive technical documentation and regulatory references
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UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
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Vehicle Certification Agency (VCA)
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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