The Peugeot XN1 is a 1,580 cc, inline‑four naturally aspirated petrol engine produced between 1985 and 1997. It features a single overhead camshaft (SOHC) design with 8 valves and a carbureted or single — point fuel injection system. This iteration of the XU engine family delivers a modest output of 55–66 kW (75–90 PS), prioritizing fuel economy and mechanical simplicity.
Fitted to models such as the 309, 405, and Partner, the XN1 engine was engineered for dependable, low —…
Production years 1985–1992 meet pre-Euro standards; 1993–1997 models typically comply with Euro 1 .
The Peugeot XN1 is a 1,580 cc inline‑four naturally aspirated petrol engineered for compact and mid‑size models (1985-1997). It combines SOHC 8-valve architecture with carburetor or single-point injection to deliver predictable, economical performance. Designed to meet pre-Euro and Euro 1 emissions standards, it prioritizes durability and ease of maintenance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,580 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, SOHC, 8‑valve | |
Aspiration | Naturally Aspirated | |
Bore × stroke | 78.5 mm × 82.0 mm | |
Power output | 55–66 kW (75–90 PS) | |
Torque | 120–130 Nm @ 3,000 rpm | |
Fuel system | Carburetor or Single-point injection (Bosch Mono-Jetronic) | |
Emissions standard | Pre-Euro (pre-1993); Euro 1 (1993 onwards) | |
Compression ratio | 9.2:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Belt-driven | |
Oil type | Refer to vehicle handbook / manufacturer specification | |
Dry weight | 115 kg |
The Peugeot XN1 was used across Peugeot's XU platform with transverse mounting. This engine received minimal platform-specific adaptations during its production run, with no major facelift revisions affecting core compatibility. All applications 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 PSA technical bulletins (1985-1997) and owner-reported failure data (1997-2023). 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 XN1 engine is renowned for its mechanical simplicity and long-term durability. Its main weakness is the ignition module, which is a cheap and easy fix. With regular timing belt changes and basic maintenance, these engines can easily surpass 300,000 km. They are considered one of PSA's most robust and economical petrol engines.
The most frequent issues are failure of the distributor's ignition module, timing belt failure if neglected, carburetor or throttle body problems causing running issues, and coolant leaks from the water pump or hoses. These are well-documented in PSA service bulletins and owner communities.
This 1.6L petrol engine was primarily used in the Peugeot 309 (1985-1993), 405 (1987-1997), and early Partner vans (1996-1997). It was also fitted to the Citroën ZX (1991-1997) as part of the PSA Group's shared engine strategy, offering a reliable and economical powertrain option.
Modest power gains are possible. Basic modifications like a performance air filter, free-flow exhaust, and a performance camshaft can yield 10-15 kW. More significant power requires engine swaps or forced induction, which is complex. It's best suited as a reliable, economical workhorse.
Real-world fuel economy is good for its era. In a Peugeot 309, expect around 9.5 L/100km in the city and 6.0 L/100km on the highway, averaging 7.5 L/100km (approx. 38 mpg UK) combined. The heavier 405 will be slightly thirstier, averaging closer to 8.0 L/100km (35 mpg UK).
Yes. The XN1 is an interference engine. If the timing belt breaks or jumps teeth, the pistons will collide with the open valves, causing severe and expensive internal engine damage. Adhering to the 90,000 km / 5-year timing belt replacement schedule is absolutely critical.
Peugeot specifies oil meeting the PSA B71 2290 standard, typically a 10W-40 mineral or semi-synthetic. This engine is not particularly demanding regarding oil. Change intervals should not exceed 15,000 km or one year. Using a high-quality 10W-40 will ensure long engine life.
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.