Alfa Romeo2001–2007Technical specifications

166 2.5: Technical specifications

Workshop data for the 2.5-litre petrol (engine code 362.01). Covers engine, fluids, brakes, service, torques and air conditioning: the figures to check before a job or a parts order.

Common faults & fixes

Summary

Match the engine code (362.01) to the vehicle before ordering parts or applying these figures.

Vehicle specifications

Overview

Make
Alfa Romeo
Model
166
Years
2001–2007
Fuel
Petrol
Engine code
362.01

Performance & efficiency

Power
138 kW (188 hp)
Engine size
2,492 cc
Cylinders
6 · DOHC
Compression ratio
10.3:1
Fuel system
Bosch

Fluids & capacities

Engine oil (with the filter)
5.9 litres
All 93 specifications below

Engine & identification

Vehicle identification

No. of cylinders Type6/DOHC
Capacity (Fiscal) cc2492
Compression ratio :110,3
Suitable for unleaded petrolYes
Minimum octane rating RON95
Ignition system MakeBosch
Ignition system TypeMotronic ME3.1
Ignition system DescriptionMap-DI
Trigger locationCam/Crankshaft
Fuel system MakeBosch
Fuel system TypeMotronic ME3.1
Fuel system DescriptionMFI-s
Air metering TypeMass
Combined ignition and fuel ECMYes
Diagnostic socketYes

Ignition system

Ignition coil supply voltage + with ballast V12,0

Firing order

The firing order for the Alfa Romeo 166 2.5 (2001–2007) is 1-4-2-5-3-6.

Firing order1-4-2-5-3-6

Valve clearances

Valve clearances on the Alfa Romeo 166 2.5 (2001–2007) are hydraulic — they self-adjust, so no manual clearance figure applies.

Valve clearance - INLET mmHydraulic
Valve clearance - EXHAUST mmHydraulic

Engine oil & fluids

Engine oil

The Alfa Romeo 166 2.5 (2001–2007) takes 5.9 litres of engine oil with the filter. The specified engine oil grade is SAE 10W-40 synthetic for all ambient temperatures, with API/ACEA classification SJ/A3.

Manual gearbox

The manual gearbox has a listed capacity of 1.6 litres. The specified oil is SAE 75W-85 synthetic, with classification GL-4.

Coolant

The listed total cooling-system capacity is 10.3 litres.

Grades, filling conditions and capacities

Lubricants and capacities — complete reference
Engine oil options
Ambient temperature range All temperatures
Engine oil grade SAE 10W-40 Synthetic
Engine oil classification API/ACEA SJ/A3
Engine with filter(s) litres 5.9
Other lubricants and capacities
Manual transmission oil grade SAE 75W-85 Synthetic
Manual transmission oil classification GL-4
Manual transmission litres 1.6
Cooling system - total capacity litres 10.3
Brake fluid Type DOT 4
Power steering fluid Type Dexron II
Power steering fluid litres 1.4

Brakes & wear limits

Brake disc thickness

Brake discs on the Alfa Romeo 166 2.5 (2001–2007) are replaced at a minimum thickness of 24,2 mm (ventilated) front and 9 mm rear.

Minimum disc thickness for replacement - ventilated Front24,2 mm
Minimum disc thickness for replacement Rear9 mm

Brake disc and drum dimensions

Minimum pad thickness Front1,5 mm
Minimum pad thickness Rear1,5 mm
Parking brake travel No. of notches1-3

Service & electrical

Ignition timing

The ignition timing on the Alfa Romeo 166 2.5 (2001–2007) is not adjustable.

Ignition timing - basic BTDC °Engine/rpmNot adjustable

Battery

The Alfa Romeo 166 2.5 (2001–2007) uses a 12 V, 100 Ah battery.

Battery V/RC(Ah)12 (100)

Tuning and emissions

Ignition advance checks °Engine/rpmECM Controlled
Idle speed rpm700±50 Not adjustable
Oil temperature °C80
CO level at idle speed - tailpipe Vol. % CO0,5 Max Not adjustable
HC level at idle speed ppm100
CO2 level at idle speed Vol. % CO214,5-16
O2 level at idle speed Vol. % O20,1-0,5
Increased idle speed for CO test rpm2500-2900
CO content at increased idle speed Vol. %0,3
Lambda at increased idle λ0,97-1,03

Starting and charging

Maximum cranking amps A690-730
Alternator output A/V/rpm120/14/3000

Service checks and adjustments

Oil pressure bar/rpm2,9-3,1/5000
Radiator cap bar0,98

Spark plugs

Spark plugs Original equipmentNGK
Spark plug TypePFR6B
Spark plugs MakeNGK
Spark plug TypePFR6B

Tightening torques

Cylinder head bolt torque

The cylinder head bolts on the Alfa Romeo 166 2.5 (2001–2007) are tightened in 2 stages: 24-26 Nm, then a final 240°.

Cylinder head
Renew boltsNo
Tighten24-26 Nm
Tighten240°
Cylinder head instructions—
Other engine tightening torques
Main bearings Renew bolts/nutsNo
Main bearings Stage 124-26 Nm
Main bearings Stage 280°
Big end bearings Renew bolts/nutsNo
Big end bearings Stage 119-21 Nm
Big end bearings Stage 250°
Oil pump to cylinder block34-42 Nm
Sump bolts13-16 Nm
Sump drain bolt64-79 Nm
Flywheel/driveplate116-129 Nm
Clutch pressure plate24-29 Nm
Crankshaft pulley/damper centre bolt200-247 Nm
Camshaft sprocket/gear68-84 Nm
Camshaft carrier/cap18-20 Nm
Camshaft/rocker cover10-13 Nm
Exhaust manifold to cylinder head22-27 Nm
Exhaust downpipe to manifold24-29 Nm
Engine coolant temperature (ECT) sensor17-21 Nm
Engine oil pressure switch20-25 Nm
Chassis tightening torques
Front hub67-73 Nm+50°
Rear hub304-336 Nm
Steering track rod end43-47 Nm
Brake disc to hub Front17 Nm
Brake caliper to carrier Front28 Nm
Brake caliper/carrier to hub Front160 Nm
Brake disc to hub Rear8-13 Nm
Brake caliper to carrier Rear28 Nm
Brake caliper/carrier to hub Rear57 Nm
Road wheels86±8 Nm

Air conditioning

No. of AC service connectors2
Air conditioning restrictor typeExpansion valve
Compressor clutch/magnetic couplingYes
Compressor variable displacement solenoidNo
Air conditioning refrigerant TypeR134a
Air conditioning refrigerant quantity grams650

Frequently asked questions

What is the firing order of the Alfa Romeo 166 2.5?

The firing order for the Alfa Romeo 166 2.5 (2001–2007) is 1-4-2-5-3-6.

How much oil does the Alfa Romeo 166 2.5 take?

The Alfa Romeo 166 2.5 (2001–2007) takes 5.9 litres of engine oil with the filter. The specified engine oil grade is SAE 10W-40 synthetic for all ambient temperatures, with API/ACEA classification SJ/A3.

What are the valve clearances for the Alfa Romeo 166 2.5?

Valve clearances on the Alfa Romeo 166 2.5 (2001–2007) are hydraulic — they self-adjust, so no manual clearance figure applies.

What is the cylinder head torque for the Alfa Romeo 166 2.5?

The cylinder head bolts on the Alfa Romeo 166 2.5 (2001–2007) are tightened in 2 stages: 24-26 Nm, then a final 240°.

What is the ignition timing for the Alfa Romeo 166 2.5?

The ignition timing on the Alfa Romeo 166 2.5 (2001–2007) is not adjustable.

What is the minimum brake disc thickness for the Alfa Romeo 166 2.5?

Brake discs on the Alfa Romeo 166 2.5 (2001–2007) are replaced at a minimum thickness of 24,2 mm (ventilated) front and 9 mm rear.

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