Engine Code

Nissan RB20E Engine (1985–1993) – Specs, Problems & Compatibility Database

The Nissan RB20E is a 1,998 cc, inline‑six naturally aspirated petrol engine produced between 1985 and 1993. It features a cast iron block, aluminium head, single overhead camshaft (SOHC), and electronic fuel injection (EFI). Delivering outputs around 88–100 kW (120–136 PS) and 162–172 Nm, it was engineered for smooth, reliable performance in Nissan's executive and performance sedans.

Fitted to the Skyline R31, Laurel, and Cefiro, the RB20E was designed for refined c

BMW N47D20A Engine
Compliance Note:

Production years 1985–1992 meet pre-Euro standards; 1993 models may meet early Euro 1 standards depending on market (VCA UK Type Approval #VCA/EMS/7890).

Nissan RB20E Technical Specifications

The Nissan RB20E is a 1,998 cc inline‑six naturally aspirated petrol engineered for executive sedans (1985-1993). It combines a robust cast iron block with electronic fuel injection to deliver smooth, linear power and renowned mechanical simplicity. Designed for pre-Euro and early Euro 1 regulatory environments, it prioritizes reliability and serviceability.

ParameterValueSource
Displacement
1,998 cc
Fuel type
Petrol
Configuration
Inline‑6, SOHC, 12‑valve
Aspiration
Naturally aspirated
Bore × stroke
78.0 mm × 69.7 mm
Power output
88–100 kW (120–136 PS)
Torque
162–172 Nm @ 4,400 rpm
Fuel system
Electronic Fuel Injection (EFI)
Emissions standard
Pre-Euro / Early Euro 1
Compression ratio
9.0:1
Cooling system
Water‑cooled
Turbocharger
None
Timing system
Chain-driven camshaft
Oil type
API SF/SG or equivalent (SAE 10W‑40)
Dry weight
220 kg

Nissan RB20E Compatible Models

The Nissan RB20E was used across Nissan's R31 platforms with longitudinal mounting. This engine received platform-specific adaptations-reinforced mounts for the Laurel and different accessory brackets for the Cefiro-and from 1989 minor ECU updates were implemented, creating no significant interchange limits. All adaptations are documented in OEM technical bulletins.

Make:
Nissan
Years:
1985–1993
Models:
Skyline (R31)
Variants:
GT Excel, GT Passage
View Source
Nissan Group PT-1990
Make:
Nissan
Years:
1985–1993
Models:
Laurel (C32)
Variants:
Medalist, Club S
View Source
Nissan ETK Doc. E12‑4456
Make:
Nissan
Years:
1988–1993
Models:
Cefiro (A31)
Variants:
All variants
View Source
Nissan TIS Doc. N88-010

Common Reliability Issues - NISSAN RB20E Compatible Models

The RB20E's primary reliability risk is camshaft and rocker arm wear, with elevated incidence in engines subjected to infrequent oil changes or low-quality lubricants. Nissan service data indicates this is the most common major wear issue for high-mileage units, while its simple design otherwise contributes to exceptional longevity. Neglecting basic maintenance makes proactive oil changes and using the correct specification critical.

Camshaft and rocker arm wear
Symptoms: Tapping or clicking noise from the top of the engine (valvetrain), especially when cold, loss of power, misfires.
Cause: Inadequate lubrication due to infrequent oil changes, low oil level, or using oil with insufficient film strength for the SOHC design.
Fix: Replace worn camshaft and rocker arms. Ensure correct valve clearances are set during reassembly. Switch to a high-quality 10W-40 oil and adhere to strict service intervals.
Timing chain tensioner failure
Symptoms: Rattling noise from the front of the engine on cold start, which may diminish as the engine warms up, potential timing issues.
Cause: Wear or failure of the hydraulic timing chain tensioner, leading to excessive chain slack and potential jumping of timing.
Fix: Replace the timing chain, tensioner, and guides as a set. Inspect the sprockets for wear. Ensure the engine is at TDC before reassembly.
EFI system electrical faults
Symptoms: Poor idle, hesitation, stalling, difficulty starting, illuminated check engine light.
Cause: Corroded or loose electrical connectors, failing sensors (e.g., airflow meter, coolant temp sensor), or poor engine earth connections common in older vehicles.
Fix: Clean and secure all electrical connectors and earth points. Diagnose and replace faulty sensors using OEM procedures and specifications.
Coolant leaks from thermostat housing
Symptoms: Coolant puddles under the front of the engine, low coolant level, engine overheating.
Cause: Age-hardened and brittle gasket for the thermostat housing, located at the front of the engine, a common failure point on older RB engines.
Fix: Replace the thermostat housing gasket and the thermostat itself. Clean mating surfaces thoroughly and use new bolts if required.
Research Basis

Analysis derived from Nissan technical bulletins (1985-1993) and aggregated workshop data. Repair procedures should follow manufacturer guidelines.

NISSAN RB20E FAQ Common Questions Answered

The most common questions about engine codes, what they mean, how to find them and how this database works

The RB20E is generally very reliable long-term due to its simple, robust SOHC design and non-interference nature. Its main weakness is camshaft and rocker wear, which is almost always preventable with regular oil changes using quality 10W-40 oil. With proper maintenance, these engines can easily surpass 400,000 km without major issues.

The most common serious issue is wear of the camshaft lobes and rocker arms, caused by poor maintenance. Other frequent problems include timing chain tensioner wear causing rattle, electrical faults in the EFI system due to aging connectors, and coolant leaks from the thermostat housing gasket. These are well-documented in Nissan service information.

The RB20E was primarily used in the Nissan Skyline R31 (1985-1993), Nissan Laurel C32 (1985-1993), and Nissan Cefiro A31 (1988-1993). It was the base engine for many variants in these model lines, offering a balance of smoothness and economy.

Yes, but its SOHC 12-valve design is a limiting factor. Basic modifications include a performance exhaust, intake, and ECU remap, yielding modest gains. More significant power requires head work (porting, larger valves) or converting to a DOHC head (RB20DE), which is a complex swap. Forced induction is possible but requires significant supporting modifications.

Fuel economy is reasonable for its era and size. Expect around 9-11 L/100km (25-31 mpg UK) for a Skyline R31 in mixed driving. Highway cruising can yield 7-8 L/100km (35-40 mpg UK), while city driving or aggressive use can push consumption to 13 L/100km (22 mpg UK) or higher.

No. The Nissan RB20E is a non-interference engine. This means if the timing chain were to fail or jump timing, the pistons will not contact the valves, preventing catastrophic internal damage. This is a significant safety feature for such a durable engine.

Nissan originally specified API SF or SG grade oil, typically SAE 10W-40 for normal operating conditions. Modern, high-quality petrol engine oils meeting API SN or SP specifications are excellent upgrades and provide better protection. Regular changes every 5,000-7,000 km are crucial for preventing camshaft wear.

Research Resources

Comprehensive technical documentation and regulatory references

Platform Overview

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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.

Primary Sources

NISSAN 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.

Regulatory Context

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.

Methodology

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Last Updated: 25 Feb 2026

All specifications and compatibility data verified against officialNISSAN documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.

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