Skoda Felicia

since 1994 release

Repair and operation of the car

Skoda Felicia
+ Cars of the Skoda Felicia brand
+ Maintenance instruction
+ Routine maintenance
+ Repair of the engine
+ Cooling systems, heating
- Power supply system
   + Power supply system of the carburetor engine of 1.3 l
   + System of the central injection (SPFI) of the petrol engine
   - System of the distributed injection (MPFI) of the petrol engine
      General information and precautionary measures
      Removal and installation of assembly of the air cleaner
      The control unit temperature of the soaked-up air - the general information
      Removal, installation and adjustment of a cable of an accelerator
      Removal and installation of components of system of injection Simos 2P
      Removal and installation of components of system of injection Magneti-Marelli 1AV
      Removal and installation of assembly of the fuel pump and sensor of measurement of fuel consumption
      Removal and installation of the fuel tank
      Dumping of residual pressure in a power supply system
      Removal and installation of the inlet pipeline
      Check of serviceability of functioning and adjustment of system of injection
      Unleaded fuel - the general information and rules of use
   + Power supply system of the diesel engine
   + Systems of decrease in toxicity and production of the fulfilled gases
+ Engine electric equipment
+ Coupling
+ Transmission
+ Power shafts
+ Brake system
+ Suspension bracket and steering
+ Body and finishing of salon
+ Onboard electric equipment

System of the distributed injection (MPFI) of the petrol engine

General information and precautionary measures

The Simos 2P and Magneti-Marelli 1AV systems concern to family of control systems of the engine of the closed type. Such systems exercise control as directly over fuel injection, and over its ignition. This Part of the Head is devoted only to power supply system components. The main components of the considered systems are among: the fuel tank with the submersible electric gasoline pump established in it, the fuel filter, lines of giving and return of fuel, the throttle case, the fuel highway, four injectors of injection of fuel, and also an electronic control unit (ECU) complete with information sensors, actuation mechanisms and a connecting electrical wiring. Both systems are almost identical each other and differ only in details of a design of the inlet pipeline and ECU.

The gasoline pump provides continuous supply of fuel via the filter of cartridge type to the fuel highway under small excessive pressure. The regulator of pressure of fuel provides a constant pressure on injection injectors. Excess of fuel on the returnable line comes back to the fuel tank. Such system of continuous giving allows to reduce temperature of fuel and to prevent its evaporation.

Opening and closing of injectors is made at the command of an electronic control unit (ECU) calculating the moment and duration of injection on the basis of the analysis of the arriving information signals of engine turns, situation and speed of movement of a butterfly valve, depression depth in the inlet pipeline, temperature of the soaked-up air, temperature of cooling liquid, composition of the fulfilled gases, etc.

The air which is soaked up in the engine passes through the air cleaner in which the filtering element made of dense paper replaceable is established. Temperature of the soaked-up air is regulated by means of the vacuum valve installed in a casing of the air cleaner and allowing to mix external air with arriving through the heater casing placed over a final collector.

Temperature of the throttle of air coming to the case is taken by the sensor installed on the inlet pipeline. In parallel the sensor traces absolute pressure in the pipeline. All information comes to ECU and is used by it when determining optimum air-fuel mix according to the current operational parameters of the engine.

Control of turns of idling of the engine is exercised of partially electronic module of provision of a butterfly valve installed from above on the throttle case, and partially - system of ignition, due to change of installations of a corner of an advancing of ignition. In view of told need for manual corrections of turns disappears and an opportunity of system is not provided by its design. Information on situation and speed of movement of a butterfly valve is delivered in ECU by the special sensor sometimes called also by a potentiometer of a butterfly valve. The sensor is located on the left wall of the case of a throttle.

Content of oxygen in the fulfilled gases continuously is traced by ECU via the l-probe installed in forward section of system of release (ahead of the catalytic converter). Analyzing the arriving information, ECU issues commands for correction of a corner of an advancing of ignition and duration of injection, forming thereby air-fuel mix, optimum on structure. As a result, need for manual correction of contents WITH in the fulfilled gases also disappears. The catalytic converter is included in a basic equipment of all models considered in the present manual.

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

It is necessary to notice that failure diagnostics of all control systems of the engine is possible only by means of the special electronic reader. In case of any violations of functioning of system it is necessary to address immediately experts company service center of the Skoda company which will make reading and interpretation of the ECU codes of the malfunctions revealed by system of self-diagnostics which are written down in the block of memory. The replacement procedure of the refused components of system is described in the following Sections of the Head.