Skoda Felicia

Since 1994 of release

Repair and car operation

Shkoda Felitsija
+ Cars of mark Skoda Felicia
+ The maintenance instruction
+ Routine maintenance
+ Engine repair
+ Systems of cooling, heating
- The power supply system
   + The power supply system of the carburettor engine of 1.3 l
   - System of the central injection (SPFI) the petrol engine
      The general information and safety measures
      Removal and installation of assemblage of an air cleaner
      The vacuum switch of a control mean in temperature of soaked up air
      Removal, installation and adjustment of a cable of an accelerator
      Removal and installation of components of system Bosch Mono-Motronic
      Removal and installation of assemblage of a gasoline pump and the gauge of the expense of fuel
      Removal and installation of a fuel tank
      Dump of residual pressure in the power supply system
      Removal and installation of the inlet pipeline
      Check of functioning and adjustment of system of injection
      Neetilirovannoe fuel - the general information and use rules
   + System of the distributed injection (MPFI) the petrol engine
   + The power supply system of the diesel engine
   + Systems of decrease in toxicity and release of the fulfilled gases
+ Engine electric equipment
+ Coupling
+ Transmission
+ Power shafts
+ Brake system
+ Suspension bracket and steering
+ Body and salon furnish
+ Onboard electric equipment


System of the central injection (SPFI) the petrol engine

The general information and safety measures

System Mono-Motronic function chart

1 — МЗамок ignitions
2 — the Storage battery
3 — the Gauge of frequency and position of a cranked shaft
4 — a l-probe
5 — the Katalitichesky converter
6 — the Coal adsorber
7 — Э/м the valve of system of catching of fuel evaporations
8 — the Fuel tank
9 — the Electric fuel pump
10 — the Fuel filter
11 — the Gauge of position throttle заслонки
12 Gauge of temperature of a cooling liquid

13 — the Air cleaner
14 — the Injector of injection of fuel
15 — the Regulator of pressure of fuel
16 — the Gauge of temperature of air
17 — the Step-by-step engine of system of idling
18 — the Spark plug
19 — the ignition Distributor
20 — ECU managements of ignition
21 — ECU injection systems
22 — Safety locks and the relay
23 — the Diagnostic socket

The scheme of functioning of an injector of injection and regulator of pressure of fuel

1 — the Supply of fuel from a gasoline pump
2 — an injection Injector

3 — the Regulator of pressure of fuel
4 — Return of fuel to a tank

System Bosch Mono-Motronic concerns family of control systems of the engine of the closed type. Such systems exercise administration as directly over fuel injection, and over its ignition.

System Mono-Motronic function chart is presented on an illustration. Into number of the basic components of system of injection enter: a fuel tank with established in it погружным an electric gasoline pump, the fuel filter, lines of giving and fuel return, the case of a throttle with the electronic injector of injection of fuel built in in it, and also the electronic block of management (ECU) complete with information gauges, actuation mechanisms and connecting electroconducting.

The gasoline pump provides continuous giving of fuel through the filter картриджного type in the throttle case under small superfluous pressure. Built in the case of a throttle the regulator of pressure of fuel provides a constant pressure on an injection injector. Surplus of fuel on a returnable line arrives back in a fuel tank. Such system of continuous giving allows to lower temperature of fuel and to prevent its evaporation.

Opening and injector closing is made at the command of ECU, calculating the moment and duration of injection on the basis of the analysis of arriving information signals about engine turns, position and speed of moving throttle заслонки, temperature of soaked up air, temperature of a cooling liquid, speed of movement of the car, structure of the fulfilled gases etc. On an illustration the scheme of functioning of an injector of injection and a regulator of pressure of fuel is presented.

Air soaked up in the engine passes through an air cleaner in which the replaceable filtering element made of a dense paper is established. The temperature of soaked up air is regulated by means of the vacuum valve established in an inlet sleeve of an air cleaner and allowing to mix external air with arriving through the casing of a heater placed over a final collector. Position заслонки the valve the thermosensitive gauge-switch established in an air cleaner operates.

The information on engine turns arrives in ECU from the gauge of the Hall established from above on картере of a transmission and fixing frequency of rotation of a flywheel.

The temperature of a throttle of air arriving in the case is measured by the gauge established directly over an injector of injection. The information arrives in ECU which on the basis of its analysis defines current requirements of the engine concerning the moment of injection and structure of an air-fuel mix.

Management of turns of idling of the engine is carried out by partially electronic module of position throttle заслонки, established from above on the throttle case, and partially - ignition system, at the expense of change of installations of a corner of an advancing of ignition. In view of told necessity for manual updatings of turns disappears also possibility its design of system is not provided. The information on position and speed of moving throttle заслонки is delivered in ECU by the special gauge sometimes called also by a potentiometer throttle заслонки. The gauge is located on the left wall of the case of a throttle.

The oxygen maintenance in the fulfilled gases is continuously traced ECU through a l-probe established in forward section of system of release. Analyzing the arriving information, ECU gives out commands on updating of a corner of an advancing of ignition and duration of injection, forming thereby optimum on structure an air-fuel mix. As a result, necessity for manual updating of the maintenance WITH in the fulfilled gases also disappears. Into a standard complete set of all models considered in the present Management enters каталитический the converter.

In addition to the listed functions, ECU exercises administration of functioning of system of catching of fuel evaporations.

It is necessary to notice that system Bosch Mono-Motronic problem diagnostics is possible only by means of the special electronic input reader. The diagnostic socket for input reader connection is located in the right part of the panel of devices of the car. In case of any infringements of functioning of system it is necessary to address immediately to experts of the firm service-centre of company Skoda who will make reading and decoding written down in the block of memory ECU of codes revealed by system of self-diagnostics of malfunctions.

The replacement procedure of the refused components of system is described in below-mentioned Sections of the Head.

Safety measures

Gasoline is an inflammable liquid in the higher measure. At performance of service of components of the power supply system it is necessary to observe special safety measures!

Do not smoke and do not come nearer to a place of work with a source of an open flame / the redurable not protected by a lamp shade! Do not make service of components of the power supply system in the premises equipped working on natural gas and heating devices equipped with a control torch. Watch, that near at hand constantly there was a charged fire extinguisher.

Avoid fuel hit in eyes and on open sites of a skin. Put on protective gloves and points. Casually got splashes wash off water with soap.
Remember that fuel evaporations not less if no more, are dangerous, than actually liquid fuel. Do not forget that the emptied container from under gasoline continues to contain steams of fuel which are not only easily flammable, but also potentially explosive!

Many of procedures described in the given Chapter are connected with necessity of a detachment of the fuel lines, inevitably conducting to fuel pouring. Try to prepare beforehand all necessary materials for gathering of spilt fuel.

Remember that residual pressure continues to be present at a system path after even long time after an engine stop. Before removal or a detachment of any of components of a fuel path the given pressure is necessary for dumping in the safe image (see Has undressed Dump of residual pressure in the power supply system).

Carrying out service of components of the power supply system special attention give to cleanliness observance - hit in a fuel path of a dirt is capable to lead to infringement of its passableness conducting to faults in work of the engine and even to its spontaneous stops.

In interests of a personal security of the executor and with a view of safety of the equipment many of procedures described in the present Chapter should be made only after a detachment from the battery of a negative wire. Such safety measure first of all excludes short circuit possibility, and in the second, allows to avoid pressure jumps in chains of an electronic part of a control system of the engine, many of which components (such as ECU, gauges and actuation mechanisms) in the higher measure are sensitive to the overloads connected with such jumps.

Let's notice, however, that the system has the known flexibility allowing it to adapt for changes of characteristics of the engine, connected with its deterioration while in service a vehicle. Such приспособляемость it is connected with presence in memory ECU of certain parametres. At battery switching-off the given information is erased and after engine start its restoration demands small expenses of time. The rehabilitation period can be accompanied by infringement of stability of turns of the engine, sensitivity decrease to change of position throttle заслонки, easy increase in the expense of fuel, etc. Duration of regenerative process is defined by frequency of use and vehicle service conditions.