Auto Manual of VW Passat B5

5.7. The basic malfunctions of a control system of the engine

THE GENERAL DATA

Before definition of malfunctions be convinced that engine start is made correctly. At start both cold, and the hot engine do not press an accelerator pedal. After start of the hot engine it is possible to increase slightly pressing of a pedal of an accelerator engine turns.

Also before definition of malfunctions be convinced that fuel is available in a fuel tank in enough, the engine has no mechanical defects, the accumulator is charged also a starter turns a cranked shaft of the engine with sufficient speed, the ignition system is serviceable, the fuel system is tight and in it there are no pollution, a ventilation hose картера pure and the tyre of grounding of the power unit is reliably connected.

Preliminary check up the malfunctions which have been written down in memory of a control system by the engine.

At work on fuel system, preliminary remove pressure in fuel system.

THE REASON	ELIMINATION METHOD
The engine is not started
At ignition inclusion the electric fuel pump does not work	Check up an electric chain of giving of pressure to the fuel pump and reliability of connection of electric sockets.
The safety lock is faulty	Check up integrity and, if necessary replace a safety lock of the fuel pump or a control mean with the engine.
The relay of the fuel pump is faulty	Check up working capacity and, if necessary, replace the relay of the fuel pump.
Pressure on fuel atomizers does not move	Check up an electric feed circuit of fuel atomizers.
The complicated start of the cold engine and work of the engine with faults
The temperature gauge is faulty	Check up and, if necessary, replace gauges of temperature of a cooling liquid and temperature of air arriving in the engine.
The engine works with faults
Unreliable contact in electric sockets of a feed circuit of the fuel pump	Check up a condition, clear and draw in contacts of electric sockets in a feed circuit of the fuel pump. Check up and, if necessary clear contacts of a safety lock and the relay of the fuel pump. Check up productivity of the fuel pump.
Pollution of the fuel filter	Replace the fuel filter
The fuel pump is faulty	Check up working capacity of the fuel pump.
The fuel atomizer is faulty	Check up and, if necessary, replace fuel atomizers.
Unstable work of the engine on transitive modes
Негерметична system of giving of air in the engine	Check up and, if necessary, tighten connections of system of giving of air in the engine.
The gauge of temperature of a cooling liquid or air arriving in the engine is faulty	Check up and, if necessary, replace gauges температу ры a cooling liquid and temperature of air arriving in the engine.
Tightness of fuel system is broken	Visually check up tightness of fuel system. Check up reliability of connections of fuel system.
The complicated start of the hot engine
Elevated pressure in fuel system	Check up pressure in fuel system and, if necessary, replace a regulator of pressure of fuel.
The pipeline of return of fuel between a regulator of pressure of fuel and a fuel tank is hammered or deformed	Clean or replace the pipeline.
Engine acceleration occurs to a delay
Негерметичны fuel atomizers	Check up and, if necessary, replace fuel atomizers.