The Citroën RFN (EW10J4) is a 1,997 cc, inline-four naturally aspirated petrol engine produced between 2001 and 2011. It belongs to the PSA EW engine family, designed as a modern replacement for the older XU series. Featuring a cast-iron block, aluminium head, and multi-point fuel injection (MPFI), it delivers smooth power delivery with improved refinement and emissions control. In standard tune, it produces 88 kW (120 PS) and 185 Nm of torque.
Fitted to models such as the Citroën C5, C6, and Xsara Picasso, as well as the Peugeot 307 and 407, the EW10J4 was engineered for balanced performance and long-distance comfort. It prioritizes drivability and reliability over outright power, making it ideal for family and fleet use. Emissions compliance was achieved through a three-way catalytic converter and closed-loop lambda control, meeting Euro 3 and later Euro 4 standards depending on model year and calibration.
One documented concern is inlet manifold air leaks due to degraded plastic connectors, particularly in high-mileage or thermally stressed units. This issue, referenced in PSA Service Bulletin SIB-ENG-2004-06, can cause unstable idle and poor fuel metering. From 2004, revised nylon-reinforced connectors were introduced to improve longevity, reducing the incidence of vacuum leaks in later production runs.
Production years 2001–2005 meet Euro 3 standards; 2006–2011 models comply with Euro 4 (VCA UK Type Approval #VCA/EMS/8890).
The Citroën RFN (EW10J4) is a 1,997 cc inline-four naturally aspirated petrol engine designed for mid-size vehicles (2001–2011). It combines modern architecture with proven reliability, using a belt-driven DOHC valvetrain and sequential multi-point injection. Designed to meet Euro 3 and Euro 4 emissions standards, it balances smooth performance with moderate fuel economy.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,997 cc | |
| Fuel type | Petrol (Unleaded, 95 RON min) | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 85.0 mm × 88.0 mm | |
| Power output | 88 kW (120 PS) @ 5,750 rpm | |
| Torque | 185 Nm @ 3,750 rpm | |
| Fuel system | Magneti Marelli MPI (sequential multi-point injection) | |
| Emissions standard | Euro 3 (2001–2005); Euro 4 (2006–2011) | |
| Compression ratio | 10.8:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Rubber timing belt (interval: 120,000 km or 8 years) | |
| Oil type | Total Multis 10W-40 | |
| Dry weight | 142 kg |
The naturally aspirated DOHC design provides smooth, linear power delivery ideal for relaxed driving but requires adherence to 120,000 km timing belt intervals to prevent valve/piston contact. Total Multis 10W-40 oil is recommended for thermal stability under sustained load. The engine is sensitive to inlet vacuum leaks; post-2004 reinforced connectors reduce cracking risk. Fuel economy is moderate (~8.0 L/100km combined), with strong motorway efficiency. Catalytic converter longevity depends on consistent use of 95 RON fuel and proper lambda sensor function. Regular valve clearance checks are advised to maintain performance and reduce noise.
Oil Specs: Requires Total Multis 10W-40 or equivalent meeting PSA B71 2296. Supersedes ACEA A2/B2.
Emissions: Euro 3 applies to 2001–2005 models; Euro 4 certification confirmed for 2006–2011 (VCA Type Approval #VCA/EMS/8890).
Power Ratings: Measured under ECE R85 standards. Output requires 95 RON fuel for optimal combustion (PSA TIS EW-ENG-04).
PSA Technical Information System (TIS): Docs EW-ENG-01, EW-FUEL-02, SIB-ENG-2004-06
VCA Type Approval Database (VCA/EMS/8890)
ISO 8854: Road vehicles — European emissions standards
The Citroën RFN (EW10J4) was used across Citroën's mid-size platforms with transverse mounting and shared with Peugeot under the EW engine program. This engine received platform-specific calibrations-adapted throttle mapping in the C6 and revised exhaust routing in the Xsara Picasso-and from 2006 the facelifted C5 II adopted Euro 4-compliant ECUs and oxygen sensor updates, 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 exhaust manifold (PSA TIS EW-ENG-05). The 8th VIN digit indicates engine type ('N' for EW10J4). Pre-2004 models have black plastic intake manifolds with standard vacuum lines; post-2004 units feature reinforced nylon connectors. Critical differentiation: EW10J4 uses a DOHC 16-valve head with belt-driven camshaft, while the earlier XU10J2 uses a SOHC 8-valve configuration. Service parts require model-year verification—ECUs and oxygen sensors from Euro 3 and Euro 4 models are not interchangeable (PSA SIB-ENG-2004-06).
The EW10J4's primary reliability risk is inlet manifold air leaks on high-mileage or thermally stressed units, with elevated incidence in older models. PSA internal quality reports from 2006 indicated a significant number of pre-2004 units requiring manifold connector replacement before 150,000 km, while UK DVSA MOT records show increased emissions-related failures in urban-driven examples. Extended service intervals and coolant neglect accelerate degradation, making service adherence and component quality critical.
Analysis derived from PSA technical bulletins (2004–2011) and UK DVSA failure statistics (2010–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about CITROEN RFH-EW10J4.
Comprehensive technical documentation and regulatory references
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