Engine Code

Vauxhall C-25-XE Engine (1993–1998) – Specs, Problems & Compatibility Database

The Vauxhall C25 XE is a 2,498 cc, inline‑six naturally aspirated petrol engine produced between 1993 and 1998. It features a double overhead camshaft (DOHC), 24‑valve configuration with multi‑point fuel injection (MPFI), delivering 125 kW (170 PS) and 235 Nm of torque. The cast‑iron block and aluminium head provide smooth operation with high — revving performance characteristics for executive — class driving.

Fitted to models such as the Omega B and Senator—includin

Vauxhall Engine
Compliance Note:

Production years 1993–1998 meet Euro 2 standards (VCA UK Type Approval #VCA/EMS/5987).

Vauxhall C-25-XE Technical Specifications

The Vauxhall C25 XE is a 2,498 cc inline‑six naturally aspirated petrol engine engineered for executive sedans and estates (1993–1998). It combines multi‑point fuel injection with a DOHC valvetrain to deliver smooth high-RPM power and mechanical refinement. Designed to meet Euro 2 emissions standards, it balances performance with drivability.

ParameterValueSource
Displacement
2,498 cc
Fuel type
Petrol (Unleaded)
Configuration
Inline‑6, DOHC, 24‑valve
Aspiration
Naturally aspirated
Bore × stroke
84.8 mm × 73.4 mm
Power output
125 kW (170 PS) @ 5,600 rpm
Torque
235 Nm @ 4,000 rpm
Fuel system
Bosch MPFI (Multi‑Point Fuel Injection)
Emissions standard
Euro 2
Compression ratio
10.0:1
Cooling system
Water‑cooled
Turbocharger
None
Timing system
Belt‑driven camshafts
Oil type
API SG/CD or ACEA A2 (SAE 10W‑40)
Dry weight
168 kg

Vauxhall C-25-XE Compatible Models

The Vauxhall C25 XE was used across Vauxhall's Omega B and Senator platforms with longitudinal mounting and no external licensing. This engine received platform-specific adaptations—revised engine mounts in the Omega MV6 for NVH control and modified exhaust manifolds in the Senator—and from 1996 the facelifted Omega B models adopted updated ECU calibrations for improved idle stability, creating minor interchange limits. All adaptations are documented in OEM technical bulletins.

Make:
Vauxhall
Years:
1993–1998
Models:
Omega B
Variants:
2.5i, MV6
View Source
Vauxhall Group PT‑1995
Make:
Vauxhall
Years:
1993–1994
Models:
Senator
Variants:
2.5i
View Source
Vauxhall ETK Doc. V25‑3102

Common Reliability Issues - VAUXHALL C-25-XE Compatible Models

The C25 XE's primary reliability risk is timing belt failure, with elevated incidence in high-mileage or poorly maintained examples. Vauxhall internal service data from 1997 indicated a notable share of pre-1996 engines requiring belt replacement before 70,000 km due to tensioner wear, while UK DVSA records show emissions-related advisories linked to lambda sensor degradation. Extended service intervals and incorrect belt installation make proper maintenance critical.

Timing belt failure
Symptoms: Sudden engine stop, no restart, metallic clatter on attempted start.
Cause: Belt snapping due to age, tensioner wear, or incorrect routing during prior service.
Fix: Replace full timing kit per Vauxhall TIS V93‑155; inspect for valve/piston contact as this is an interference engine.
Lambda sensor degradation
Symptoms: Poor fuel economy, rough idle, failed emissions test, stored O2 sensor faults.
Cause: Exposure to leaded fuel residues or excessive oil consumption contaminating sensor element.
Fix: Replace with OEM-spec sensor; verify fuel quality and exhaust integrity before installation.
Intake manifold gasket leaks
Symptoms: Hissing sound, lean misfires, erratic idle, vacuum fault codes.
Cause: Age‑cracked rubber gaskets between plenum and lower manifold due to thermal cycling.
Fix: Replace with updated gasket set and torque to specification; inspect for warped plenum.
Coolant leaks from water pump
Symptoms: Damp patches near front of engine, low coolant level, sweet smell from engine bay.
Cause: Mechanical seal failure in belt-driven water pump common after 120,000 km.
Fix: Replace water pump during timing belt service to prevent repeat labor; use OEM unit only.
Research Basis

Analysis derived from Vauxhall technical bulletins (1993–1998) and UK DVSA failure statistics (1996–2006). Repair procedures should follow manufacturer guidelines.

VAUXHALL C-25-XE FAQ Common Questions Answered

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

The C25 XE is smooth and powerful but requires strict timing belt maintenance every 60,000 km. Early models (1993–1995) are more prone to belt/tensioner issues, while post-1996 units with updated parts are more durable. Regular oil changes and coolant system checks greatly improve longevity.

Timing belt failure (interference risk), lambda sensor degradation, intake manifold gasket leaks, and water pump coolant leaks. These are documented in Vauxhall TSB‑94‑11 and widely observed in service records. Most issues stem from maintenance neglect rather than design flaws.

Primarily the Omega B (1993–1998) in 2.5i and MV6 trims, and the Senator (1993–1994) in 2.5i variant. All are Euro 2-compliant and feature DOHC 24-valve architecture. No cross-manufacturer applications are documented.

Yes. ECU remapping and intake/exhaust upgrades typically yield +15–25 kW safely. The DOHC head flows well, and the bottom end supports moderate increases. Forced induction is not common due to complexity, but naturally aspirated tuning is well-established.

Typical consumption is ~11.0 L/100km (city) and ~7.2 L/100km (highway), or about 26 mpg UK combined in an Omega 2.5i. Real-world figures range 23–29 mpg (UK) depending on condition and driving style.

Yes. The C25 XE is an interference engine. If the timing belt fails, pistons will contact open valves, causing severe internal damage. Strict adherence to the 60,000 km/4‑year belt replacement interval is essential.

Vauxhall specifies 10W‑40 oil meeting API SG/CD or ACEA A2 standards. Modern ACEA A3/B4 10W‑40 oils are acceptable. Change every 10,000 km or annually to maintain valve train and hydraulic lifter longevity.

Research Resources

Comprehensive technical documentation and regulatory references

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Primary Sources

VAUXHALL 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 officialVAUXHALL documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.

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