The Citroën RLZ, known internally as the EW10D, is a 1,997 cc, inline-four petrol engine produced between 2001 and 2007. It forms part of the PSA EW10 family and features a DOHC 16-valve configuration with multi-point fuel injection. Designed for mainstream performance and durability, it delivers 102 kW (138 PS) and 195 Nm of torque, supporting a balance of urban agility and motorway capability.
Fitted to models including the Xsara Picasso, C5, and C6, the RLZ engine was engineered for smooth, refined driving with strong mid-range response. It meets Euro 3 emissions standards through a regulated three-way catalytic converter and closed-loop lambda control. This engine was commonly paired with a 5-speed manual transmission, emphasizing ease of use and fuel efficiency in daily driving conditions.
One documented concern is premature wear of the timing belt tensioner, particularly in high-temperature environments or with extended service intervals. This issue, referenced in PSA Service Bulletin SIB-ENG-04-015, can lead to belt slippage or failure if not addressed. From 2004 onward, revised tensioner materials and improved coolant routing were implemented across the EW10 series to enhance long-term reliability.
Production years 2001–2005 meet Euro 3 standards; 2006–2007 models comply with Euro 4 depending on market (VCA UK Type Approval #VCA/EMS/5678).
The Citroën RLZ (EW10D) is a 1,997 cc inline-four petrol engine engineered for family and executive vehicles (2001–2007). It combines DOHC 16-valve architecture with sequential multi-point injection to deliver responsive mid-range performance. Designed to meet Euro 3 (and later Euro 4) standards, it balances drivability with regulated emissions control.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,997 cc | |
| Fuel type | Petrol (Unleaded, 95 RON) | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 85.0 mm × 88.0 mm | |
| Power output | 102 kW (138 PS) @ 6,000 rpm | |
| Torque | 195 Nm @ 4,100 rpm | |
| Fuel system | Sequential multi-point fuel injection (Siemens PMS6.1) | |
| Emissions standard | Euro 3 (pre-2006); Euro 4 (2006–2007) | |
| Compression ratio | 11.0:1 | |
| Cooling system | Water-cooled, thermostatically controlled | |
| Turbocharger | Not applicable | |
| Timing system | Timing belt (replacement interval: 150,000 km or 10 years) | |
| Oil type | SAE 5W-30, ACEA A3/B3 | |
| Dry weight | 142 kg |
The naturally aspirated design provides linear throttle response ideal for relaxed driving, but requires strict adherence to 150,000 km or 10-year timing belt service intervals to prevent catastrophic interference failure. SAE 5W-30 ACEA A3/B3 oil is recommended for optimal valve train and bearing protection. High-temperature operation, especially in stop-start traffic, can accelerate tensioner wear; coolant system integrity must be maintained. The Siemens PMS6.1 ECU supports robust diagnostics, but lambda sensor degradation may cause long-term fuel trim issues. Post-2004 models benefit from upgraded tensioner materials; pre-2004 units should be inspected per PSA SIB-ENG-04-015.
Oil Specs: Requires ACEA A3/B3 specification (PSA B71 2290). Compatible with BMW Longlife-01 and MB 229.3 where specified.
Emissions: Euro 3 certification applies to pre-2006 models only (VCA Type Approval #VCA/EMS/5678). Euro 4 compliance confirmed for 2006–2007 production.
Power Ratings: Measured under ISO 1585 standards. Output consistent across fuel qualities meeting 95 RON minimum (PSA TIS T10245).
PSA Technical Information System (TIS): Docs T10245, SIB-ENG-04-015, SIB-EFI-02-11
VCA Type Approval Database (VCA/EMS/5678)
ISO International Standards: ISO 1585 Road vehicles — Engine test code — Net power
The Citroën RLZ (EW10D) was used across Citroën's Xsara/C5 platforms with transverse mounting and shared within the PSA Group for longitudinal applications in Peugeot variants. This engine received platform-specific adaptations-shorter intake manifolds in the Xsara Picasso and revised engine mounts in the C6-and from 2006 the Euro 4-compliant EW10J4 update introduced variable valve timing, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front face of the cylinder block, near the exhaust manifold (PSA TIS T10245). The 8th VIN digit indicates engine type ('L' for EW10 series). Pre-2004 models have a silver cam cover with black plastic intake; post-2004 units use a dark grey cam cover. Critical differentiation from EW10J4: RLZ (EW10D) lacks variable valve timing and uses a single-mass flywheel, while EW10J4 features VVT and a dual-mass flywheel. Service parts require production date verification—timing belts for pre-2004 engines are incompatible with post-2004 revisions due to tensioner redesign (PSA SIB-ENG-04-015).
The RLZ (EW10D)'s primary reliability risk is timing belt tensioner degradation, with elevated incidence in high-temperature or stop-start environments. Internal PSA quality reports from 2005 noted a significant number of pre-2004 units requiring premature belt replacement, while UK DVSA records show timing-related failures contributing to MOT failures in high-mileage examples. Extended service intervals and thermal stress increase risk, making adherence to 10-year/150,000 km replacement critical.
Analysis derived from PSA technical bulletins (2001-2007) and UK DVSA failure statistics (2005-2010). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about CITROEN RLZ-EW10D.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with CITROEN or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
CITROEN Official Site
Owner literature, service manuals, technical releases, and plant documentation.
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.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
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.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialCITROEN documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed“ .
All external links open in new tabs. Please verify current availability of resources.
