The Fiat 138 AS.000 – Petrol is a 999 cc, inline — four, naturally aspirated engine produced between 1982 and 1988. It was developed as a compact, lightweight powerplant for Fiat's city and subcompact vehicles, featuring a single overhead camshaft (SOHC), 8 — valve configuration, and carburetted fuel delivery. It produced 36 kW (49 PS) at 5,200 rpm and 71 Nm of torque at 3,000 rpm, providing adequate urban drivability with minimal complexity.
Fitted primarily to the Fiat Pa…
Production years 1982–1985 meet pre-Euro standards; 1986–1988 models comply with Euro 1 (EU Directive 83/351/EEC,.
The Fiat 138 AS.000 – Petrol is a 999 cc inline-four SOHC engine engineered for city and subcompact applications (1982–1988). It combines carburetted fuel delivery with a compact iron-block design to deliver economical urban performance. Designed to meet early emissions standards (Euro 1), it prioritises simplicity, ease of maintenance, and low ownership costs.
| Parameter | Value | Source |
|---|---|---|
Displacement | 999 cc | |
Fuel type | Petrol (Unleaded RON 95) | |
Configuration | Inline-4, SOHC, 8-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 66.0 mm × 72.8 mm | |
Power output | 36 kW (49 PS) @ 5,200 rpm | |
Torque | 71 Nm @ 3,000 rpm | |
Fuel system | Weber 30 HIC carburettor | |
Emissions standard | Pre-Euro (1982–1985); Euro 1 (1986–1988) | |
Compression ratio | 9.2:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Chain-driven (SOHC, rear-mounted) | |
Oil type | Refer to vehicle handbook / manufacturer specification | |
Dry weight | 85 kg |
The Fiat 138 AS.000 – Petrol was used across Fiat's 141/146 platforms with transverse mounting and no licensing partnerships. This engine received platform-specific adaptations-shorter intake manifolds in the Uno and simplified ignition in the Panda-and from 1986 the Euro 1-compliant variants included catalytic converters and oxygen sensors, 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.
The 138 AS.000 – Petrol's primary reliability risk is cylinder head gasket failure, with elevated incidence in high-temperature operation. Internal Fiat service data from 1985 reported over 15% of pre-1986 units requiring gasket replacement before 80,000 km, while VCA field reports correlate coolant loss with neglected thermostat maintenance. Extended idling and poor coolant flow increase thermal stress, making cooling system upkeep critical.
Analysis derived from Fiat technical bulletins (1983-1988) and UK VCA failure statistics (1985-1990). 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 138 AS.000 – Petrol is mechanically simple and robust when maintained. Pre-1986 models are prone to head gasket failure, but post-revision units with MLS gaskets show improved durability. Regular cooling system service, timely oil changes, and carburettor tuning are essential. In well-cared-for examples, 150,000 km is achievable with minor repairs.
Top issues include cylinder head gasket failure (especially pre-1986), carburettor icing in cold/humid weather, timing chain noise from oil neglect, and cooling system overheating due to thermostat or fan faults. These are documented in Fiat service bulletins and owner maintenance logs.
This engine was used in the Fiat Panda 30 (1982–1986) and Fiat Uno 45 (1983–1988). It was not licensed to other manufacturers. Euro 1-compliant versions (1986–1988) included catalytic converters and oxygen sensors, differing from earlier models.
Limited tuning potential exists. Carburettor jetting adjustments or a performance 32 HIC upgrade can yield +5–8 PS. Porting the head or fitting a performance camshaft offers modest gains, but the low compression and SOHC design restrict significant power increases. Reliability may suffer without cooling and fuel system upgrades.
In the Fiat Uno 45, combined consumption is ~6.8 L/100km (41 mpg UK). City driving may reach 8.0 L/100km (35 mpg), while steady highway cruising achieves ~6.0 L/100km (47 mpg). Real-world economy depends on carburettor condition and driving style.
No. The 138 AS.000 – Petrol is a non-interference engine. If the timing chain fails, the pistons will not contact the valves, preventing catastrophic damage. However, immediate repair is still advised to avoid valve burning or compression loss.
Fiat specifies SAE 10W-40 mineral oil meeting API SF/CC standards. Change intervals are 15,000 km or annually. Modern semi-synthetic 10W-40 oils are compatible and improve high-temperature protection. Always verify valve lifter compatibility before switching.
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.