Alfa Romeo1997–2001

156 2.5: Common faults & known problems

Common faults & known problems

20 known faults documented in workshop bulletins. Of these, six concern the engine and fuel system and four the brakes. Symptoms, causes, repair steps and part numbers are shown where supplied.

Technical specifications

Engine & fuel system

6 documented faults — symptoms, causes and workshop fixes.

Engine malfunction indicator lamp (MIL) illuminated

Overview

Affects
All models, →01/01.

Symptoms

Random/single misfire.

Cause

Intermittent connection at multi-plug between accelerator pedal position (APP) sensor and engine control module (ECM).

Repair

  1. Check for diagnostic trouble codes and delete as necessary.
  2. Remove multi-plug and join wires permanently by soldering.

Data: Motorwise Workshop. Bulletin 5.

Engine overheating at high vehicle speed

Affects All models.

Cause

Coolant pump impeller cracked.

Repair

  1. Replace coolant pump.

Data: Motorwise Workshop. Bulletin 6.

Water ingress into front footwells

Overview

Affects
All models.

Symptoms

No obvious sign of coolant leakage.

Cause

AC evaporator drain tube blocked by bulkhead sound proofing.

Repair

  1. Cut hole in bulkhead sound proofing to provide outlet for AC evaporator drain tube.
  2. Ensure AC evaporator drain tube not damaged.

Data: Motorwise Workshop. Bulletin 9.

Poor driveability

Affects All models.Fit new part

Symptoms

Intake noise from engine area. Lack of power.

Cause

Intake air pipe between air filter and throttle body split.

Repair

  1. Fit new intake air pipe.

Data: Motorwise Workshop. Bulletin 11.

Engine malfunction indicator lamp (MIL) illuminated

Affects All models with 1.9D JTD (937A2.000) engine.P1604Software update

Symptoms

Trouble code stored: P1604.

Cause

Engine control module (ECM) software fault.

Repair

  1. Re-program ECM with modified software.

Data: Motorwise Workshop. Bulletin 15.

Engine malfunction indicator lamp (MIL) illuminated

Affects All models with petrol engines.P0325P1325

Symptoms

Trouble codes stored: P0325, P1325.

Cause

Knock sensor (KS) fault.

Repair

  1. Check wiring connector and resistance of KS. Replace parts as necessary.

Data: Motorwise Workshop. Bulletin 18.

Brakes

4 documented faults — symptoms, causes and workshop fixes.

Poor brake servo assistance after cold start

Insufficient vacuum at low speed after cold start.

Overview

Affects
All models, with AT (Q-System).

Symptoms

Brake pedal stiff during initial braking after cold start.

Repair steps

  1. Inspect vacuum intake system type.
  2. If necessary, replace with modified vacuum intake pipe and corrugated intake hose.
  3. View View more information RH:.

Parts

Parts listed in the bulletin
PartPart numberQty
Vacuum intake pipe606647121
Vacuum intake pipe606647151
Corrugated intake hose6066739191
Collar131261701
Collar131267701

Data: Motorwise Workshop. Bulletin 1.

Front brakes vibrating when brakes applied at medium to high speed

Affects All models, →2000

Cause

Front brake disc distortion.

Repair

  1. Replace front brake pads and brake discs.
Parts4 parts
Parts listed in the bulletin
PartPart numberQty
Ventilated disc606585652
Solid disc606585672
Brake pads - ventilated disc99483341
Brake pads - solid disc99483351

Data: Motorwise Workshop. Bulletin 4.

Squeal from rear brakes

Overview

Affects
All models.
Remedy
Clean & lubricate

Cause

Pads seize in brake caliper carrier due to corrosion and dirt ingress.

Repair

  1. Remove and clean rear brake pads.
  2. Clean brake caliper carrier and lubricate.

Data: Motorwise Workshop. Bulletin 10.

Squeaking noise from rear brakes

Affects All models.

Cause

Handbrake cable sticking due to internal damage/corrosion.

Repair

  1. Replace both handbrake cables.

Data: Motorwise Workshop. Bulletin 14.

Suspension & drivetrain

3 documented faults — symptoms, causes and workshop fixes.

Knocking noise from front suspension over uneven surfaces

Affects All models.Fit modified part

Cause

Excessive play between front inner anti-roll bar bushes and bush clamps.

Repair

  1. Fit modified front anti-roll bar.

Data: Motorwise Workshop. Bulletin 16.

Knocking/squeaking noise from rear suspension over uneven surfaces

Rear suspension lower arm bushes worn. Fix: fit a new part.

Overview

Affects
All models.
Remedy
Fit new part

Repair steps

  1. Mark position of rear suspension lower arm inner bolt.
  2. Fit new rear suspension lower arms.
  3. Realign marks and check rear wheel alignment.

Data: Motorwise Workshop. Bulletin 17.

Knocking/squeaking noise from rear suspension over uneven surfaces

Affects All models.

Cause

Rear trailing arm hub assembly bushes.

Repair

  1. Replace both rear trailing arm hub assembly bushes.

Data: Motorwise Workshop. Bulletin 19.

Steering

1 documented fault — symptoms, causes and workshop fixes.

Buzzing noise from power steering high-pressure pipe

Overview

Affects
All models →1999.
Parts
2 parts

Cause

Faulty retaining bolt/valve on power steering.

Repair

  1. Replace retaining bolt/valve with modified version.
  2. Bleed power steering system.
Parts2 parts
Parts listed in the bulletin
PartPart numberQty
Retaining bolt/valve608075751
Seal102824602

Data: Motorwise Workshop. Bulletin 2.

Clutch & gearbox

1 documented fault — symptoms, causes and workshop fixes.

Occasional loss of drive

Affects All models with auto shift manual (ASM) transmission.P1769

Symptoms

Trouble code stored in transmission control module (TCM) fault memory: P1769.

Cause

ASM transmission shift actuator accumulator faulty.

Repair

  1. Replace ASM transmission shift actuator accumulator.

Data: Motorwise Workshop. Bulletin 20.

Air conditioning & heating

2 documented faults — symptoms, causes and workshop fixes.

Outlet air distribution/temperature does not correspond to setting

Affects All models with automatic temperature control (ATC).

Cause

Ignition switched ON immediately after reconnection of battery.

AC/heater air mix flap motor and AC/heater air direction motor position cycle interrupted.

Repair

  1. Disconnect battery, reconnect and wait at least 2 minutes before switching ignition ON.

Data: Motorwise Workshop. Bulletin 3.

Engine coolant blower motor only works on second blower speed

Overview

Affects
All models, 1997-02.
Remedy
Clean & lubricate

Symptoms

Engine malfunction indicator lamp (MIL) illuminated.

Cause

Failure of engine coolant blower motor resistor.

Repair

  1. Check and clean engine coolant blower motor resistor multi-plug terminals.
  2. Replace engine coolant blower motor resistor.

Data: Motorwise Workshop. Bulletin 12.

Body & trim

2 documented faults — symptoms, causes and workshop fixes.

Bonnet not opening or closing correctly

Affects All models.Clean & lubricate

Cause

Bonnet catch seized.

Repair

  1. Clean and lubricate bonnet catch.

Data: Motorwise Workshop. Bulletin 7.

Noise sounds as though it is coming from behind instrument cluster/fascia, but can be difficult to pin-point

Overview

Affects
All models.

Cause

Sound proofing touching fascia support panel.

Repair

  1. Remove fascia or windscreen.
  2. Cut sound proofing away to avoid contact with fascia support brackets.

Data: Motorwise Workshop. Bulletin 13.

Wipers & visibility

1 documented fault — symptoms, causes and workshop fixes.

Noise from lower windscreen area

Overview

Affects
All models.
Remedy
Clean & lubricate

Cause

Dry contact surfaces on front suspension upper arm bushes.

Front suspension upper arm bushes worn.

Repair

  1. Check front suspension upper arm bushes for excessive play.
  2. Replace or lubricate front suspension upper arm bushes as necessary.

Data: Motorwise Workshop. Bulletin 8.

Glossary

Technical terms used in this guide.

MIL
Malfunction indicator lamp — the engine warning light on the dashboard
ECM
Engine control module — the electronic unit that manages the engine
Trouble Codes
Standardised fault codes stored by the engine control module, read with a diagnostic tool
AC
Air conditioning — the system that cools the cabin
ATC
Automatic temperature control — climate control that holds the temperature you set
KS
Knock sensor — listens for engine knock so the engine control module can retard the timing
RH
Right-hand — the right side of the vehicle as you sit in it
TCM
Transmission control module — the electronic unit that manages the gearbox
AC/Heater
The heating and air-conditioning system
Accelerator Pedal Position
The sensor that tells the engine control module how far the accelerator is pressed
Actuator
A motor or solenoid that moves a mechanical part on command
Anti-Roll Bar
A bar that links the left and right suspension to cut body roll in corners
Caliper
The part that squeezes the brake pads onto the disc
Control Module
A control unit for one of the vehicle's systems (engine, gearbox, brakes, body, and so on)
Fascia
The dashboard and the surrounding interior panel
Fault Memory
The list of stored trouble codes in a control module
Multi-Plug
A multi-pin electrical connector on a wiring harness
Re-Program
Update the software on a control module using the manufacturer's diagnostic tool
Trouble Code
A standardised fault code stored by a control module, read with a diagnostic tool
Blower Motor
The fan that pushes air through the heater and air-conditioning
Bush
A rubber mounting that lets a suspension or body joint move without metal-to-metal contact
Bushes
Rubber mountings that let a suspension or body joint move without metal-to-metal contact
Evaporator
The air-conditioning heat exchanger in the dashboard that cools the cabin air
Lower Arm
A suspension link that locates the wheel at the bottom of the hub
Misfire
One or more cylinders not firing correctly — the engine runs roughly or loses power

Frequently asked questions

What are the common faults with the Alfa Romeo 156 2.5?

This guide contains 20 workshop bulletins for the Alfa Romeo 156 2.5. Of these, six concern the engine and fuel system and four the brakes. Symptoms, causes, repair steps and part numbers are shown where supplied.

Does every Alfa Romeo 156 2.5 have these faults?

No. These are patterns documented across the model by workshops, not predictions for an individual vehicle. Where a fault applies only to certain vehicles or VIN ranges, that is listed with the fault.

Can I check for Alfa Romeo 156 2.5 faults myself?

Many of them. The documented symptoms can be seen, heard or felt during a test drive.

Related guides

Glossary term

See in the glossary →