Engine & identification
Vehicle identification
| No. of cylinders Type | 4/DOHC |
|---|---|
| Capacity (Fiscal) cc | 1970 |
| Suitable for unleaded petrol | Yes |
| Minimum octane rating RON | 95 |
| Ignition system Make | Bosch |
| Ignition system Type | Motronic M1.5.5 |
| Ignition system Description | Map-DI |
| Trigger location | Cam/Crankshaft |
| Fuel system Make | Bosch |
| Fuel system Type | Motronic M1.5.5 |
| Fuel system Description | MFI-s |
| Air metering Type | Mass |
| Combined ignition and fuel ECM | Yes |
| Diagnostic socket | Yes |
Ignition system
| Ignition coil supply voltage + with ballast V | 12,0 |
|---|---|
| Primary resistance Ohm | 0,5 |
Firing order
The firing order for the Alfa Romeo 166 2.0 (1998–2001) is 1-3-4-2.
| Firing order | 1-3-4-2 |
|---|
Valve clearances
Valve clearances on the Alfa Romeo 166 2.0 (1998–2001) are hydraulic — they self-adjust, so no manual clearance figure applies.
| Valve clearance - INLET mm | Hydraulic |
|---|---|
| Valve clearance - EXHAUST mm | Hydraulic |
Engine oil & fluids
Engine oil
The Alfa Romeo 166 2.0 (1998–2001) takes 4.4 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.
See the reference table for the complete manual gearbox entries and their conditions.
Coolant
The listed total cooling-system capacity is 8.0 litres.
Grades, filling conditions and capacities
| 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 | 4.4 |
| 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 | 8.0 |
| Brake fluid Type | DOT 4 |
| Power steering fluid Type | Dexron II |
Brakes & wear limits
Brake disc thickness
Brake discs on the Alfa Romeo 166 2.0 (1998–2001) are replaced at a minimum thickness of 24,2 mm (ventilated) front and 9 mm rear.
| Minimum disc thickness for replacement - ventilated Front | 24,2 mm |
|---|---|
| Minimum disc thickness for replacement Rear | 9 mm |
Brake disc and drum dimensions
| Minimum pad thickness Front | 1,5 mm |
|---|---|
| Minimum pad thickness Rear | 1,5 mm |
Service & electrical
Ignition timing
The ignition timing on the Alfa Romeo 166 2.0 (1998–2001) is not adjustable.
| Ignition timing - basic BTDC °Engine/rpm | Not adjustable |
|---|
Tuning and emissions
| Ignition advance checks °Engine/rpm | ECM Controlled |
|---|---|
| Idle speed rpm | 850±30 Not adjustable |
| Oil temperature °C | 80 |
| CO level at idle speed - tailpipe Vol. % CO | 0,5 Max Not adjustable |
| HC level at idle speed ppm | 100 |
| CO2 level at idle speed Vol. % CO2 | 14,5-16 |
| O2 level at idle speed Vol. % O2 | 0,1-0,5 |
| Increased idle speed for CO test rpm | 2500-2900 |
| CO content at increased idle speed Vol. % | 0,3 |
| Lambda at increased idle λ | 0,97-1,03 |
Starting and charging
| Battery V/RC(Ah) | 12 |
|---|---|
| Alternator output A/V/rpm | 120/14/3000 |
Service checks and adjustments
| Oil pressure bar/rpm | 1,0-1,5/850 |
|---|---|
| Radiator cap bar | 0,90-1,00 |
| Thermostat opens °C | 85 |
Fuel system
| System pressure bar | 3,3-3,7 |
|---|---|
| Lambda sensor (Oxygen) heater Ohm | 8,5-9,5 |
Spark plugs
| Spark plugs Original equipment | NGK |
|---|---|
| Spark plug Type | BKR6EKPA/PMR7A |
| Electrode gap mm | 0,8-0,9 |
| Spark plugs Make | NGK |
| Spark plug Type | BKR6EKPA/PMR7A |
| Electrode gap mm | 0,8-0,9 |
Tightening torques
Cylinder head bolt torque
The cylinder head bolts on the Alfa Romeo 166 2.0 (1998–2001) are tightened in 5 stages: 20 Nm, then 40 Nm, then 90°, then 90°, then a final 90°.
| Cylinder head | |
|---|---|
| Renew bolts | No |
| Tighten | 20 Nm |
| Tighten | 40 Nm |
| Tighten | 90° |
| Tighten | 90° |
| Tighten | 90° |
| Cylinder head instructions | — |
|---|---|
| Other engine tightening torques | |
| Main bearings Renew bolts/nuts | No |
| Main bearings Stage 1 | 48-55 Nm |
| Main bearings Stage 2 | 96-119 Nm |
| Big end bearings Renew bolts/nuts | No |
| Big end bearings Stage 1 | 22-27 Nm |
| Big end bearings Stage 2 | 44-53 Nm |
| Sump bolts | — |
| Sump bolts | |
| Sump drain bolt | 17-21 Nm |
| Flywheel/driveplate | 121-149 Nm |
| Clutch pressure plate | 24-29 Nm |
| Crankshaft pulley/damper centre bolt | 340-378 Nm |
| Camshaft sprocket/gear | — |
| Camshaft sprocket/gear | |
| Camshaft carrier/cap | 13-16 Nm |
| Camshaft/rocker cover | 10 Nm |
| Inlet manifold to cylinder head | 17-21 Nm |
| Exhaust manifold to cylinder head | 17-21 Nm |
| Spark plugs | — |
| Spark plugs | |
| Lambda sensor (Oxygen) | 45 Nm |
| Knock sensor (KS) | 20 Nm |
| Chassis tightening torques | |
| Front hub | — |
| Front hub | |
| Rear hub | 304-336 Nm |
| Steering track rod end | 43-47 Nm |
| Brake caliper/carrier to hub Front | 160 Nm |
| Brake disc to hub Rear | 8-13 Nm |
| Brake caliper/carrier to hub Rear | 57 Nm |
| ABS sensor Front | 4-6 Nm |
| ABS sensor Rear | 4-6 Nm |
| Road wheels | 86±8 Nm |
Air conditioning
| No. of AC service connectors | 2 |
|---|---|
| Air conditioning restrictor type | Expansion valve |
| Compressor clutch/magnetic coupling | Yes |
| Compressor variable displacement solenoid | No |
| Air conditioning refrigerant Type | R134a |
| Air conditioning refrigerant quantity grams | 700 |
| Air conditioning oil group | PAG |
| Air conditioning oil Type | SP10 |
| Air conditioning oil quantity cm³ | 135 |
| Air conditioning oil viscosity ISO | 46 |
Frequently asked questions
What is the firing order of the Alfa Romeo 166 2.0?
The firing order for the Alfa Romeo 166 2.0 (1998–2001) is 1-3-4-2.
How much oil does the Alfa Romeo 166 2.0 take?
The Alfa Romeo 166 2.0 (1998–2001) takes 4.4 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 2.0?
Valve clearances on the Alfa Romeo 166 2.0 (1998–2001) are hydraulic — they self-adjust, so no manual clearance figure applies.
What is the cylinder head torque for the Alfa Romeo 166 2.0?
The cylinder head bolts on the Alfa Romeo 166 2.0 (1998–2001) are tightened in 5 stages: 20 Nm, then 40 Nm, then 90°, then 90°, then a final 90°.
What is the ignition timing for the Alfa Romeo 166 2.0?
The ignition timing on the Alfa Romeo 166 2.0 (1998–2001) is not adjustable.
What is the minimum brake disc thickness for the Alfa Romeo 166 2.0?
Brake discs on the Alfa Romeo 166 2.0 (1998–2001) are replaced at a minimum thickness of 24,2 mm (ventilated) front and 9 mm rear.