The Citroën RLZ (XU10J4) is a 1,998 cc, inline — four, naturally aspirated petrol engine produced between 1992 and 2001. It is part of the PSA XU engine family, known for durability and smooth operation in mid — size vehicles. Featuring multi — point fuel injection (MPFi), DOHC, and 16 valves, it produces 99 kW (135 PS) at 6,000 rpm and 187 Nm at 4,000 rpm, delivering refined performance ideal for executive and family — oriented applications.
Fitted to models such as the Xantia,…

Production years 1992–1996 meet Euro 2; 1997–2001 models comply with Euro 3 standards .
The Citroën RLZ (XU10J4) is a 1,998 cc inline-four naturally aspirated petrol engine designed for mid-size and executive vehicles (1992–2001). It combines multi-point fuel injection with a dual overhead camshaft layout to deliver smooth, linear performance. Engineered to meet Euro 2 and Euro 3 emissions standards, it prioritizes refinement and reliability over high output.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,998 cc | |
Fuel type | Petrol (Unleaded, 95 RON min) | |
Configuration | Inline-4, DOHC, 16-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 86.0 mm × 85.8 mm | |
Power output | 99 kW (135 PS) @ 6,000 rpm | |
Torque | 187 Nm @ 4,000 rpm | |
Fuel system | Siemens Simos 3P MPFi | |
Emissions standard | Euro 2 (1992–1996); Euro 3 (1997–2001) | |
Compression ratio | 10.3:1 | |
Cooling system | Water-cooled, belt-driven water pump | |
Turbocharger | Not applicable | |
Timing system | Timing belt (DOHC) | |
Oil type | Total Multis 10W-40 | |
Dry weight | 132 kg |
The Citroën RLZ (XU10J4) was used across Citroën's XM and Xantia platforms with transverse mounting and shared with Peugeot derivatives. This engine received platform-specific tuning—reinforced mounts in the XM and revised intake manifolds in the Xantia—and from 1997 the facelifted Xantia adopted Euro 3-compliant variants with updated ECU mapping, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Engine Finders UK Ltd, which operates EngineCode.uk, can pass your enquiry to engine suppliers in the UK. The service is for vehicles in the United Kingdom, with UK delivery or fitting. This is a commercially connected service, and sending an enquiry does not confirm diagnosis or compatibility.
Diagnostic reminder: If a technician has recommended replacing the engine, you can send an enquiry to engine suppliers in the UK. Confirm the diagnosis first: an engine-code record does not diagnose a fault.
Field reports and technical service bulletins highlight component wear patterns under high-load operation. Adherence to manufacturer service intervals and approved fluid specifications is critical for long-term reliability.
Analysis derived from manufacturer technical service bulletins and industry workshop records. Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The XU10J4 is generally reliable, especially post-1996 models with revised cam chain tensioners and oil systems. Early units (1992–1995) are prone to tensioner wear if oil changes are delayed. With proper maintenance—especially timing belt replacement every 60,000 km—these engines can exceed 200,000 km. Urban drivers should prioritize oil quality and change intervals to prevent wear.
Primary issues include cam chain tensioner wear (especially pre-1996), timing belt failure if neglected, intake manifold coking, and catalytic converter degradation. These are documented in PSA service bulletins and linked to oil quality, maintenance intervals, and driving patterns. Regular servicing with correct oil and timely belt changes mitigates most risks.
The XU10J4 was used in the Xantia (2.0i 16v), XM (2.0i 16v), and late BX (2.0i 16v) from 1992 to 2001. It was also shared with Peugeot (405, 406) and used in the Citroën Synergie. Euro 2 and Euro 3 variants exist, with emissions compliance depending on model year. All are transverse-mounted on the PF1 platform.
Limited tuning potential exists due to its naturally aspirated design. ECU remapping offers minimal gains. Performance upgrades typically include performance camshafts, high-flow exhaust, and intake modifications, adding 15–25 kW. However, such modifications may compromise reliability and emissions compliance. The engine is best suited for stock reliability rather than performance tuning.
Official combined figures range from 8.2–9.1 L/100 km (~34–31 mpg UK). Real-world consumption is typically 10.0–12.0 L/100 km (~28–23 mpg UK), depending on driving style. The Xantia and XM achieve best economy on motorways. Using 95 RON fuel maintains optimal efficiency and prevents knocking under load.
Yes. The XU10J4 is an interference engine. If the timing belt fails or skips, pistons will contact open valves, resulting in severe engine damage. Any sign of belt wear or noise must be addressed immediately. Replacement at 60,000 km or 5 years is mandatory to prevent catastrophic failure.
PSA specifies Total Multis 10W-40 (or equivalent meeting PSA B71 2290). This oil ensures proper lubrication of the cam chain and valve train. Oil must be changed every 15,000 km or annually to prevent sludge and wear. Using incorrect viscosity or low-quality oil increases risk of tensioner failure, especially in pre-1996 models.
Comprehensive technical documentation and regulatory references
EngineCode.uk is operated by Engine Finders UK Ltd. It provides engine-reference information and an optional commercial enquiry service. It is not an official manufacturer website. Check the record's sources and confirm vehicle-specific details before relying on it for parts, repairs or replacement.
Our editorial standard prioritises relevant manufacturer documentation and official regulatory sources. The sources and verification status for a record should be checked alongside the data.
A statement is not verified merely because a source is listed. Where supporting evidence is missing or conflicting, the record should identify that limitation. Please report unsupported or inconsistent information.
Transparency in gaps
A missing or unverified value does not mean the manufacturer has withheld it. We distinguish information not yet verified, information not available to us, and information explicitly not disclosed by the source.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Records are subject to review and correction. Source links, dates and verification notes should be read with the technical information. Our Editorial and Sourcing Policy explains our standards and review process.
Found an error or missing source? Report a problem with this page. Include the field or statement concerned and a supporting source if available. You can also email corrections@enginecode.uk.
Copyright and permissions
Images and other material may be protected by copyright. Attribution does not by itself grant permission to reuse material. If you believe material on this site infringes your rights, contact copyrights@enginecode.uk with the page URL and details of your claim. We will review the material and take appropriate action.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
Our Privacy Policy explains how Engine Finders UK Ltd uses information from visits, vehicle lookups, enquiries and messages. Our Cookie Policy explains cookies and similar technologies and how to change your choices.
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
Ownership and commercial services
EngineCode.uk is owned and operated by Engine Finders UK Ltd. Alongside our reference content, we offer an optional replacement-engine enquiry service through Engine Finders and may identify relevant services provided by businesses connected with us. These commercial connections are disclosed. Using an enquiry service is not required to read our reference content.
Engine Finders UK Ltd operates this website. Our optional enquiry service has a commercial purpose. Our Ownership and Commercial Disclosure explains the relationship between the reference website and that service. Participating suppliers pay a fee or subscription to participate on the network and receive quote requests.
Use this record as a starting point for identification. Specifications and vehicle applications may contain errors or omissions. Confirm the exact engine variant and compatibility using vehicle-specific documentation and a qualified supplier or technician.
All external links open in new tabs. Please verify current availability of resources.