Audi A4

Since 1994 of release

Repair and car operation

Audi А4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ Exhaust system
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and channels всасывания
+ Injection system
+ Coupling
+ Transmission and the main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tyres
+ The electrotechnical equipment
- Ignition system
   That provides ignition
   When there is an ignition of a toplivno-air mix?
   Different systems of ignition
   So there is an ignition spark
   Executive office
   System brain
   The signals arriving in the block of management
   Detonation adjustment
   Be cautious in circulation with ignition
   Works on ignition system
   Search of malfunctions in ignition
   The ignition distributor
   High voltage knot
   Replacement of spark plugs
   Correct choice of spark plugs
   Check of the moment of ignition
+ Illumination
+ The alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics

Replacement of spark plugs

For replacement of spark plugs in the engine capacity of 92 kw it is necessary to disconnect a socket (1) on the terminal cascade of capacity and to unscrew the terminal cascade together with ignition coils. By arrows screws are shown. At installation consider an order of a lining of a wire: the wire from the back coil (2) goes to 2 cylinder (4); a wire from the forward coil (3) – to 1 cylinder (5).

The maintenance service plan provides replacement of candles through each 60 000 km or every three year – depending on that comes earlier. The Time interval warns occurrence of defect at the expense of ageing at small run.

Audi provides very big interval in maintenance service which can be observed only in case of use of admissible types of candles. Therefore there is occasion no it to extend even more. On a working condition of system of ignition it is necessary to pay special attention in the event that in cars is каталитический the converter – we already spoke about it.

It is necessary to examine the dismantled candles critically: further you will read, about what tells the person of a candle.

If sometimes candles are unscrewed for check: it is desirable not to clean a candle a hand. It harms изоляционному to a layer of an intermediate electrode of a spark plug (стеатит).

Dismantle of spark plugs


  1. The engine of 1,8 l and the six-cylinder engine: dismantle an engine cover.
  2. The engine of 1,8 l capacity of 92 kw: unscrew and take out coils of ignition with the terminal cascade of capacity; remove sockets of candles.
  3. The engine of 1,8 l capacity of 110 kw: unscrew and remove separate coils of ignition.
  4. At dismantle of sockets of coils of ignition do not pull a wire, and undertake a socket.
  5. Unscrew spark plugs and combine them in sequence of cylinders that it was possible to draw conclusions on a condition of a candle of the corresponding cylinder.
  6. If candles sit very strongly do not apply force, differently it is possible to strip a thread candles in a head of the block of the cylinders, made of easy metal.
  7. Warm up the engine and now unscrew candles.
  8. At installation do not screw up densely cold candles in разогретую a head of the block of cylinders, differently they will sit then, as riveted.
  9. Spark plugs should be screwed up on 30 Nanometers. If is not present near at hand динамометрического a key:
  10. Screw up a candle so that the sealing ring adjoined – it cannot be turned without application of force a hand, a key for candles.
  11. Довинтите now a new candle a special key precisely on a quarter of a turn is stronger.
  12. The candle which was in the use, it is possible довинчивать only approximately on 15 .

Spark plugs should be tightened on 30 Nanometers. If near at hand is not present динамометрического a key: screw up a candle so that the sealing ring (arrow) adjoined – in this case it cannot be tightened a hand or a key without application of force. Now, if a candle new, tighten its key precisely on a turn quarter. If the candle was in the use turn its key only approximately on 15 , it is enough of it.

 Councils: to increase sliding of a carving of a spark plug, you can наскрести in coils of a few graphite from a soft simple pencil or grease them медесодержащей with greasing a little. Oil or greasing "will bake" a spark plug in a carving of a head of the block of cylinders.

The person of a spark plug

Spark plugs in certain degree are witnesses of process of combustion in the engine. On appearance of a top of a candle (the person of a candle) can be defined, how much optimum works the engine. It is preliminary necessary to warm up thoroughly the car on rural road or on a highway. Check after movement on short distance can lead to a wrong conclusion. Look at a top of an insulator with an average electrode and on lateral electrodes:

  • Top of an insulator of light grey or brownish colour: correct installation of system of injection, the engine works economically.
  • Strong adjournment: the reason can be in additives in engine oil, either in fuel, or in the raised expense of oil. Change oil or fuel mark.
  • The adjournment of black colour similar to soot: at the expense of frequent movement on short distances the candle does not reach self-cleaning temperature, wrong калильное number.
  • Top of an insulator of whitish colour: the ignition moment is too strongly shifted towards "advancing", electronic adjustment of the moment of ignition or a detonation sensor control does not work.
  • The melted off sites on an average and lateral electrodes: накальное ignition as a result of a deposit in the combustion chamber, перегретые the valves, incorrectly established point of ignition, defective adjustment of a point of ignition or stagnation of heat as a result of insufficient cooling.
  • Destruction of a top of an insulator, at an initial stage appreciable in the form of hair cracks: detonation combustion because of poor quality fuel, wrong installation of ignition, defective adjustment of a point of ignition, a defective sensor control of the detonation, insufficient cooling of the engine or pauperisation of a toplivno-air mix at the expense of collateral air.
  • Yellowish brilliant layer on an insulator top: adjournment at the expense of additives in gasoline and engine oil which at sharp full loading have passed to the engine in a liquid state were formed and became electrowire and as consequence – faults in ignition. At trips on short distances week you should not subject the engine to full loading at once.
  • Butter layer on electrodes and an internal surface of candles: defect of rings of the pistons, directing valves or linings of cores of valves.
  • If in appearance of a spark plug any features are not appreciable, but the engine badly is started or twitches, nevertheless the reason can be in candles. During start of the cold engine invisible cracks in a ceramic insulator can be filled by a condensate of fuel which takes away an ignition spark. Under the pressure of a candle too can refuse, though in the dismantled condition it is visible, as the spark slips. In a doubtful case replace.

Distance between electrodes

The toplivno-air mix and the fulfilled gases promote corrosion of metal electrodes of spark plugs. And the high voltage at проскакивании sparks tears off from them the smallest particles of metal therefore the distance between electrodes of spark plugs in due course increases. In the presence of candles with three electrodes the ignition spark can "find" the shortest way. Therefore almost it is not required to turn in electrodes.