Paul, first of all, I really wound not trust this dealer with your car. The fact they don't have the correct infomation to look at, let alone a clue how to fix the problem, speaks volumes to me.
Any how mate, take a look at the following, along with the attachments, print it off and hopefully the ECU dude will have a better idea.
P.S. you owe me a Guinness!!
An electronic management system supervises and governs all engine parameters. It optimises performance and fuel consumption by responding in real time to different service conditions.
The system is managed by a single control unit that controls the twin spark ignition (static and lost spark), and the injection (phased).
The system uses signals received from numerous sensors to control
actuators. It is connected to the following systems:
» accelerator pedal;
engine cooling system;
exhaust with catalytic converter;
fuel vapour recirculation.
On this version, the engine is fitted with a throttle body controlled electronically by the control unit. Special softare in the engine management control unit computes throttle opening; This dispenses with the need for a mechanical connection between the accelerator pedal and the throttle body.
Fuel injection system Supply lines to the control unit and the various system components (sensors and actuators) are protected by a special maxifuse and another protects the steering wheel fuses, located with the relays in the services area (behind the engine bulkhead).
The engine control unit M10 monitors and controls the entire electronic ignition and
The control unit is supplied directly by the battery via a line protected by maxifuse CENTR
of B5 at pin 4 of connector B of M10 via fuse F20 of junction unit B1.
The main relay J10 controls the entire system: it is supplied directly by the battery via the line of maxifuse B80; it is energized by an ignition-operated signal (INT/A) from the line protected by the fuse F16 of the junction unit B1; the main relay J10 consequently sends a supply:
to pin 2 of connector A of control unit M10;
to injectors N70;
to coils A30;
to timing sensor K47, via a line protected by fuse B40.
to air flow meter K41, via a line protected by fuse B40;
to the vapour recovery solenoid valve L10, via the line protected by fuse B40;
to Lambda probe heater K40, via a line protected by fuse B40; The ignition-operated power supply (INT/A) also supplies fuel pump relay J15, which is excited by a control signal (earth) from pin 29 of connector C of control unit M10. This supplies power - via fuse F3 of junction unit B1 to fuel pump N40, which is earthed through inertia switch ISO, which cuts off the circuit in the case of impact to prevent the danger of fuel flowing out.
Pins 3, 7 and 8 of connector A of control unit M10 are earthed and used as references: the first two for the ignition and the third for the injectors. Pin 8 of connector F is also earthed.
Control unit M10 receives signals from the various sensors in order to monitor all engine service conditions.
Rpm sensor K46 supplies information on engine speed via a frequency signal sent to pins 37 and 38 of connector E of control unit M10.
Timing sensor K47 receives a reference earth from pin 39 of connector E of control unit M10 and sends back a frequency signal corresponding to the timing to pin 40 of the same connector.
Engine temperature sender unit K36 receives a reference earth from connector E of control unit M10 and supplies a signal proportional to the coolant temperature to pin 29 of control unit connector E. The same sender unit also supplies information to the temperature gauge and warning light ( Wiring diagram E4010 INSTRUMENT PANEL). Hot lambda probe K40 provides control unit M10 with information on the correct composition of the air-fuel mixture. The signal is sent to pin 32 of control unit connector C, while pin 31 provides a reference earth signal. Probe K40 is heated by a resistor in order to ensure it works efficiently even when cold, the resistor is supplied by the relay J10 and receives the heating signal from pin 5 of connector A of M10.
Knock sensors K50 and K51 provide information on knock status via frequency signals sent to pins 42 and 44 respectively of control unit connector E. An earth signal is sent from pins 41 and 43 of connector E of M10 respectively.
Air flow meter K41 (supplied by relay J10) receives a reference voltage from pin 46 of connector E and sends to pin 47 of the same connector a signal proportional to air flow. K41 also contains an air temperature sensor: the sensor reference earth is supplied by pin 48 of connector E of M10, while pin 45 of connector E receives an air temperature signal.
Accelerator pedal K55 is fitted with two built-in potentiometers (a main one and a safety
back-up). The first receives power and earth from pins 22 and 23 respectively of
connector C of M10 and sends a corresponding signal to pin 24 of the same connector.
The second receives power and earth from pins 27 and 26 respectively of connector C of
M10 and sends a corresponding signal to pin 25 of connector C.
Pin 14 of connector D of M10 receives a signal from brake light switch ISO,
ignition-operated (INT/A) through a line protected by fuse F1 in junction unit B1 ( Wiring
diagram E2021 STOP LIGHT)
Pin 19 of connector D of M10 receives an earth signal from the clutch pedal switch 131.
The injectors N70 receive a power supply to enable opening from main relay J10.
The engine management unit sends commands to the injectors from pins 25, 13, 1, 26,
14 and 2 of the connector, for cylinders 1, 2, 3, 4, 5 and 6 respectively.
Control unit M10 also controls coils A30 via control signals for the coil primary windings,
while the secondary winding sends a pulse to the spark plugs: pins 20, 6, 17, 13, 19 and
5 of connector F control ignition coils 1, 2, 3, 4, 5 and 6. The coil A30 main windings
receive the go ahead supply for opening from the main relay J10.
Throttle body actuator K75 is fitted with two built-in potentiometers connected in parallel:
they control throttle opening via a stepper motor.
The motor receives information from pins 1 and 2 of connector F of M10. Pin 33 of
connector E sends a power supply to both potentiometers, pin 32 of connector E supplies
an earth signal to the potentiometers, while pins 31 and 34 of the same connector receive
signals from throttle body actuator N75.
Fuel vapour recovery solenoid L10 allows fuel vapours to pass through to the engine
intake where they join the mixture entering the combustion chamber. Valve L10, supplied
by main relay J10 (via fuse B40), is opened by the control unit when the engine is under
load via a duty-cycle signal from pin 21 of connector C of M10.
The control unit M10 is connected to the ALFA ROMEO CODE control unit M20 via a
specific serial line from pin 39 of connector C; so if the ALFA ROMEO CODE does not
detect a correct code, it does not give enablement and the engine is not started.( Wiring
diagram E7010 CODE).
The control unit is equipped with a self-test system that may be used by connecting the
unit to connector R10: this receives indirect signals from control unit M10 via a serial line
from control unit M20 described above.(pin 39 of connector C).
The self-diagnostic system also generates a signal - from pin 21 of connector F - to the
injection failure warning light on instrument panel E50. This signal leaves control unit
M10, while pin 15 of connector A of E50 supplies an ignition-operated power supply
(INT/A) from a line protected by fuse F1 of junction unit B1.
The speedometer signal (car speed) reaches pin 13 of connector D of control unit M10 (
Wiring diagram E4010 INSTRUMENT PANEL), the signal is generated by the ABS
control unit M50.
Control unit M10 sends the instrument - via pin 38 of connector C - a signal proportional
to engine rpm ( Wiring diagram E4010 INSTRUMENT PANEL).
Control unit M10 is connected to the air conditioning system via pins 4 and 21 of
connector E. This allows engine idling speed to be adjusted to increased engine load
whenever the compressor is activated, or to turn off the compressor in the case of high
speeds or high engine loads ( Wiring diagram E6021 COMPRESSOR ACTIVATION).
The control unit also controls the engine cooling system: pin 6 of connector A, 3 of
connector D and 15, 17 of connector E control activation of the relevant fan ( Wiring
diagram E5020 ENGINE COOLING).
Control unit M10 is connected to the electronic automatic transmission (EAT) via pins 5
and 17 of connector D ( Wiring diagram E7050 AUTOMATIC TRANSMISSION
Pins 11 and 12 of connector D of control unit M10 are connected to the ABS/ASR control
unit via CAN line ( Wiring diagram E7021ASR/TCS).
Pins 20, 21, 22, 23, 24 of connector D and pin 10 of connector E of control unit M10 are
connected to Cruise Control; ( Wiring diagram E5060 CRUISE CONTROL).
Pin 28 of connector C and pins 23 and 24 of connector E of control unit M10 are
connected to the electronic throttle opening system ( Wiring diagram E5065 SPORT
Some versions are fitted with supplementary connector R51 for connection to the control
unit. This is located in the engine bay.
This connection is used solely at the Production Plant and SHOULD UNDER NO
CIRCUMSTANCES be used during servicing.