Saab 9-5

Since 1997 of release

Repair and car operation

The power supply system of petrol engines

Principle of functioning of a control system of fuel injection

The general information

Fuel is sucked in from a fuel tank by the electric fuel pump and moves through the fuel filter to a fuel distributive highway. The pressure regulator provides pressure maintenance in fuel system at level 3.0 атм.

Through electrooperated injectors fuel импульсно is injected into the inlet pipeline located directly ahead of inlet valves of the engine. The engine management block makes consecutive management of injectors according to ignition order, regulates injection time and by that quantity of injected fuel.

Air necessary for formation of a fuel mix, is sucked in by the engine through the air filter and arrives through throttle заслонку, воздухораспределитель and the inlet pipeline to inlet valves. The quantity of soaked up air is regulated throttle заслонкой, resulted by a cable from a gas pedal. The volume of soaked up air is defined by the gauge of an air stream (MAF). For increase in capacity of the engine it is established турбокомпрессор, resulted by a stream of final gases.

The engine management block defines optimum time of ignition, the moment of injection and quantity of injected fuel in coordination with other systems of the car.

The information from other gauges and the operating pressure arriving to executive powers, provide optimum work of the engine in any situation. If some gauges fail, the management block is switched in a mode of the emergency program to exclude possible damage of the engine and to provide the further movement of the car.

The arrangement of components of control systems is specified by petrol engines on illustrations.

Arrangement of components of a control system of the 4-cylinder engine

1 — the Gauge of position of a pedal of gas (APP)
2 — the Gauge of position of a pedal of a brake (BPP) – on a pedal тормоза*
3 — the Gauge of position of a cranked shaft (CKP)
4 — the Diagnostic socket (DLC) – under the panel of devices, from outside водителя*
5 — the engine management Block (ECM) – models with the left wheel
6 — the engine management Block (ECM) – models with the right wheel
7 — the engine management Relay – in assembly in салоне*
8 — the Gauge of temperature ОЖ (ECT)
9 — the Valve of 1 purge of an adsorber of system EVAP
10 — the Valve of 2 purges of an adsorber of system EVAP – for локером the right lobby wheel арки*
11 — the Gauge of pressure of steams of system EVAP – in fuel баке*
12 — the Fuel filter – behind, in the right bottom углу*
13 — the Regulator of pressure of fuel
14 — the Fuel pump – in fuel баке*
15 — the Relay of the fuel pump – in the assembly block in салоне*
16 — the Ljambda-probe 1 – before каталитическим преобразователем*

17 — the Ljambda-probe 2 – for каталитическим the converter (models with two ljambda-probes) *
18 — the ignition Coil – in the module зажигания*
19 — the ignition Module
20 — Injectors
21 — the Gauge of temperature of soaked up air (IAT)
22 — the detonation Gauge – in the module зажигания*
23 — Э/м the emergency operation valve
24 — the Relay э/м the emergency operation valve – in the assembly block in салоне*
25 — the pressure Gauge in the inlet pipeline (MAP)
26 — the Gauge of volume of soaked up air (MAF)
27 — the E/motor of a drive throttle заслонки
28 — the Gauge of position of a drive throttle заслонки
29 — Perepusknoj капан турбокомпрессора
30 — the pressure Gauge in турбокомпрессоре
31 — the Valve of adjustment of target port турбокомпрессора
32 — the Gauge of speed of the car (VSS, forward right) – on a rotary fist of a wheel

* On an illustration are not designated

Arrangement of components of a control system of engine V6

1 — the Gauge of position of a pedal of gas (APP)
2 — the Gauge of position of a pedal of a brake (BPP) – on a pedal тормоза*
3 — the Gauge of position of a pedal of coupling (CPP) – on a pedal сцепления*
4 — the Gauge of position of a cranked shaft (CKP)
5 — Д/В темпостата (on a brake pedal) *
6 — the Diagnostic socket (DLC) – under the panel of devices, from outside водителя*
7 — the engine management Block (ECM) – models with the left wheel
8 — the engine management Block (ECM) – models with the right wheel
9 — the engine management Relay – in the main thing assembly блоке*
10 — the Gauge of temperature ОЖ (ECT)
11 — the Valve of 1 purge of an adsorber of system EVAP
12 — the Valve of 2 purges of an adsorber of system EVAP – behind, in the right bottom corner, model since 2000 вып. (VIN since 040000) *
13 — the Gauge of pressure of steams of system EVAP – in a fuel tank, model since 2000 вып. (VIN since 040000) *
14 — the Fuel filter – behind, in the right bottom углу*
15 — the Regulator of pressure of fuel
16 — the Fuel pump – in fuel баке*
17 — the Relay of the fuel pump – in the main thing assembly блоке*
18 — the Dokatalitichesky ljambda-probe – before каталитическим преобразователем*

19 — the Ljambda-probe 2 – for каталитическим the converter, models since 2000 вып. (VIN since 040000) *
20 — the ignition Coil – in each module зажигания*
21 — the Forward module of ignition
22 — the Back module of ignition
23 — Injectors
24 — the Gauge of temperature of soaked up air (IAT)
25 — the detonation Gauge – in each module зажигания*
26 Э/м the emergency operation valve
27 — the Relay э/м the emergency operation valve – in the main thing assembly блоке*
28 — the Gauge of absolute pressure in the inlet pipeline (MAP)
29 — the Gauge of volume of soaked up air (MAF)
30 — the Pump подмешивания air (SAI), models since 2000 вып. (VIN since 040000)
31 — the Relay of pump SAI, model since 2000 вып. (VIN since 040000) – in the main thing assembly блоке*
32 — the E/motor of a drive throttle заслонки
33 — the Gauge of position of a drive throttle заслонки
34 — the Switch of modes АТ
35 — the Gauge of speed of the car (VSS, forward right) – on a rotary fist of a wheel

* On an illustration are not designated

The scheme power supply system and release ОГ components are resulted on illustrations.

The scheme of an inlet air path and path of release ОГ of 4-cylinder engines

1 — the Control valve
2 — the Filtering element
3 — Gauge MAF
4 — Turbokompressor
5 — Interkuler
6 — Perepusknoj the valve
7 — Э/м the valve
8 — the throttle Case
9 — the Gauge of pressure of forced air/gauge IAT
10 — Gauge MAP
11 — the Engine
12 — the Oil separator of system of ventilation картера

13 — Control valves
14 — the purge Valve
15 — system EVAP Adsorber
16 — the Valve of final port
17 — the Regulator of forced air
18 — the Control valve of forced air
19 — the Ljambda-probe
20/21 — Forward/back каталитический the converter
22/23 — the Forward/back muffler
24 — the Vacuum amplifier of brakes
25 — the Servo-driver of brakes
26 — the Control valve

The scheme of giving of fuel of petrol engines on an example of the 4-cylinder engine


1 — the Fuel tank 2 — the Fuel pump 3 — the Fuel filter 4 — the Submitting fuel line	5 — the Fuel distributive highway 6 — the Injector 7 — a pressure Regulator 8 — the Returnable fuel line

The short description of principles of functioning of some of gauges and actuation mechanisms of a control system of the engine

The gauge of position throttle заслонки (TPS) is built in in the executive mechanism throttle заслонки and gives out on ECM the information on current coal of position throttle заслонки. The second potentiometer informs ECM the data on base value and forms a spare signal at failure of a potentiometer throttle заслонки.

The gauge of position of a cranked shaft (CKP) hands over to the block of management the information on number of turns of a cranked shaft and a finding of the piston of the first cylinder in ВМТ.

The gauge of temperature of a cooling liquid (ECT) represents the resistor with the negative temperature factor which resistance decreases with temperature growth.

The gauge of measurement of weight of air (MAF) represents термоанемометрический the measuring instrument which has been built in in an inlet air path of the engine, and is used ECM at definition of parametres of a dosage of an air-fuel mix.

The system of ventilation of a fuel tank/catching of fuel evaporations (EVAP) consists of a coal adsorber and э/м the valve of management of a purge of the last. In an adsorber steams of fuel formed as a result of its heating accumulate. At engine work the fuel evaporations which have accumulated in an adsorber are extended in an inlet path and go to combustion chambers.

Ljambda-probes measure the oxygen maintenance in the fulfilled gases (ОГ) before and after каталитических converters and transmit corresponding signals in the engine management block.