Audi 80/Avant (B4)

since 1991-1995 of release

Repair and car operation


Audi 80/Avant
+ Technical specification
- Engines
   Basic elements
   Greasing system
   Case ventilation
   Visual check of the engine
   Running in of the new engine
   Engine service life
   Nominal and maximum frequency of rotation
   Restriction of frequency of rotation
   Measurement of pressure of compression
   List of malfunctions
   Provorachivaniye of the engine
   Hydraulic pushers
   Works on the GRM gear belt
   List of malfunctions
   Removal and installation of a head of the block of cylinders
   Removal and engine installation
+ System of production of the fulfilled gases
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ injection System
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrosystem
+ ignition System
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications



List of malfunctions

Too low pressure of compression

Evenly low pressure of compression not necessarily is a disturbing sign; the reason can be and measuring admissions of various control devices. However it is necessary to reflect, if between separate indicators of cylinders differences more than 2 — 3 bar are measured. It can mean:

  • Wear of pistons and piston rings.
  • Zakoksovyvaniye of piston rings because of formation of deposits.
  • Development (ellipsnost) in cylinders as a result of jamming of pistons.
  • Deposits on cores or saddles of valves because of the combustion or oil remains.
  • The burned-down valves. In most cases leaky adjacent valves are at the bottom of insufficient pressure of compression and, thereby, the reduced engine capacity. To help trouble it is possible only major maintenance of a head of the block of cylinders.

Search of malfunctions

More precisely to define malfunction at low pressure of compression (a low compression), it is necessary to apply the following cunning: to dig in an opening for a spark plug it is a little oil from a butterdish and once again to measure pressure.

  • If indicators still low, the reason – valves.
  • If you received higher indicators, the reason are piston rings or, it is possible, as well cylinders. The added oil created for short time the best consolidation between pistons and walls of cylinders so the compressed gas could not disappear from there almost.

Test of system for tightness

More exact results can be received after system check on tightness which some workshops can lead. For this purpose compressed air direct to the combustion chamber through openings of spark plugs.

If the checked chamber of combustion loses pressure, it can be seen on a scale of the control device. Rather big place of leak can be distinguished listening:

  • Blares near a branch pipe of an exhaust pipe indicate the leaky final valve.
  • If air leaves the case of the air filter, means, the inlet valve is faulty.
  • In case of defective laying of the block of cylinders or a crack in a head of the block of cylinders the compressed air comes to light from the next opening of a spark plug or from an open broad tank with cooling liquid.
  • Worn-out walls of cylinders, mirrors of cylinders or piston rings pass air in a case, from where it leaves through open branch pipes for a nalivaniye of oil or on directing tube oil щупа.