Audi A4

since 1994 release

Manual of the car



Audi A4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ System of an exhaust
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and channels of absorption
+ System of injection
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tires
+ Electrotechnical equipment
+ System of ignition
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics


7c8a7ef4



Search of malfunctions

In our search of malfunctions we recognize that in the engine there are no mechanical damages. We assume that the power plant involuntarily stops or is not got any more.

The starter turns the engine?

If it does not do it or does slowly, read, please, below the section "Source of Malfunctions — the Electrotechnical Equipment". On the contrary, if the engine is quickly started, then to narrow a circle of search of malfunctions, you have to answer the following questions serially.

Spark plugs give a spark?

Remove the candle socket, unscrew a candle, insert into the candle socket. Connect I shine with an auxiliary wire with the engine block so that to provide conductivity (in the drawing the auxiliary wire was lowered for the sake of presentation). Do not touch a wire of ignition and a candle – danger of accident! If yes, clear the following question. If is not present, read further the section "Source of Malfunctions — Ignition".

Fuel comes to system of injection?

Disconnect a fuel hose in the place of its screw connection in a motive compartment (the photo above – the four-cylinder engine with a working volume of 1,8 l, the photo below – the six-cylinder engine). Be careful: fuel can scatter. Therefore when unscrewing a hose enclose a thick rag under screw connection. Extend the giving fuel-supply line with a suitable hose and lower in capacity. Let your assistant will turn a starter the engine.

If gasoline arrives, then the fuel pump works normally. If is not present, read about this situation further in the section "Source of Malfunctions — Fuel Supply". Then the fuel injection remains a source of malfunction. Or the pump works, but creates insufficient pressure.

In the beginning visual control

  • The wire socket on knots of system of ignition or in knot of system of injection was disconnected?
  • Check durability of fastening of a wire of ignition on the ignition coil, on the distributor (the engine of 1,6 l 74 kW) and on sockets of candles (ignition do not include at all!).
  • All hoses of the lowered pressure in a motive compartment are put on the corresponding branch pipe?
  • Water condensate on a cover of the distributor and in it (only at the engine of 1,6 l 74 kW)? All details of system of ignition, including the ignition coil, have to be pure and dry, otherwise there is a danger of emergence of creeping currents and breakdowns of tension.
  • Gasoline smell in a motive compartment? The fuel hose is untight or it in general was disconnected?

Source of malfunctions – the electrotechnical equipment

  • Control bulbs on the control panel do not burn or do not blink at the included ignition: the accumulator was completely discharged or accumulator plugs are disconnected.
  • Control bulbs die away at activization of a starter: the accumulator was strongly discharged, or grew old, or short circuit in a starter.
  • Control bulbs at turn of a key grow dull a little, the starter is not turned: the electromagnetic switch gets jammed, or it is faulty, or the starter is faulty.
  • Control bulbs brightly burn or blink at turn of a key; the starter is not turned: defect of contact of the plug of 50 V the ignition lock, was disconnected a wire of the plug 50 of the electromagnetic switch or the electromagnetic switch is faulty.

Source of malfunctions – ignition

  • All sockets in the field of the coil (coils) of ignition and the distributor of ignition (the engine of 1,6 l 74 kW) are correctly connected?
  • Cracks in the case of the coil of ignition or in cases of coils of ignition, signs of burns from sparks at breakdowns?
  • Only at 74 kW engine of 1,6 l: uncover the distributor. Traces of creeping currents on its inside are visible? The graphite brush in the middle of a cover faultlessly springs? There is a yar-medyanka on pins of contacts?
  • As the last measure only full check of system of ignition will help.

Source of malfunctions – fuel supply

  • There is no gasoline in the fuel tank - it is not such absurd as you, maybe, will think. In our engines with injection the lack of fuel is shown in the form of interruptions in operation of the engine on turns in the beginning.
  • The fuel pump is faulty.
  • The fuel filter got littered.
  • At normal supply of fuel – for example, at constant problems with start of the engine – suspicion falls on system of injection.