Catalytic converter. BMW the 5th E28/E34 series (from 1981 to 1993 of release)
Repair of BMW E28 and series E34 from 1981 to 1993
1. Cars of the BMW brand of 5-series
2. Engine
3. Cooling system
4. Power supply system
5. Ignition system
6. Control systems of the engine and decrease in toxicity of the fulfilled gases
7. System of production of the fulfilled gases
7.1. General information about service of system of release
7.2. Catalytic converter
8. Coupling
9. Manual box of gear shifting (RKPP) and automatic transmission (AT)
10. Transmission line
11. Steering and suspension bracket
12. Brake system
13. Body
14. Control body sizes
15. Heater and air conditioner
16. System of onboard electric equipment
17. Routine maintenance of the car
18. Size table and adjusting data
19. Schematic electric circuits
20. Governing bodies and operation receptions
21. System of onboard diagnostics - a principle of functioning and codes of malfunctions


7.2. Catalytic converter

Though the catalytic converter belongs to components of system of decrease in toxicity of the fulfilled gases, it is considered here as structurally is a part of system of release. Always check the converter when for survey and service of system of release lift the car.

General description

For decrease in allocation of not burned down hydrocarbons (NANOSECOND), a carbon monooxide (WITH) and nitrogen (NOX) oxides cars of the late models described in this management, are equipped with the catalytic converter. The converter contains the ceramic cellular store covered with precious metals which accelerate reaction between the polluting substances specified above, and oxygen in the fulfilled gases. Polluting substances are oxidized with formation of water (H2O), nitrogen and dioxide (CO2).

The typical catalytic converter (it is shown for the M10 engine, others - are similar).



  1. Visually check the converter (converters) on existence of cracks or damage. Be convinced that all seagulls and turns are hardly tightened.
  2. Check isolating cover (if it is established), welded on the converter - it should be strongly fixed.

If the isolating cover has dents so it concerns the converter case, there can be a floor overheat.

  1. Start the engine and leave it idling.
  2. Check leakages of the fulfilled gases through converter flanges. Check existence of openings in cases of all converters.

Replacement of components


  1. Lift the car and establish it on props.
  2. Examine the catalytic converter in search of cracks or damages.
  3. Check density of connections of the converter.
  4. Check the isolating casing welded over the catalytic converter for protection against damages and reduction of loading from fastening.

If the isolating casing of pro-mints so that it concerns the internal case of the converter, to a floor superfluous heat can be transferred.

  1. Start the engine and leave it to idle. Check all connections of system of release on existence of leakages of the fulfilled gases.

Measures of precautions

The catalytic converter is the reliable and simple device, which itself does not demand service, but there are some circumstances with which it is necessary to familiarize if serviceable operation of the converter during all service life interests.

  1. Do not apply etilirovanny gasoline on the car with the catalytic converter - lead will settle on precious metals, reducing efficiency and destroying the converter.
  2. Always support system of ignition and fuel system according to requirements of the manufacturer as Routine maintenance of the car is specified in Head. In particular, do not forget to replace in time filtering element of an air purifier, the fuel filter (if it is established) and spark plugs. If воздушно / a fuel mix too rich, not burned down fuel gets to the catalytic converter, overheating an element and destroying the converter.
  3. If the engine passes flashes, do not use the car at all (or as little as possible), yet do not eliminate malfunction - the admission of flash leads to hit in the converter of not burned down fuel that leads to an overheat described above.
  4. Do not get the car towage or “from a push” - thus not burned down fuel which will cause an overheat after engine start will get to the catalytic converter - look (b) and (c).
  5. Do not switch off ignition on high turns of the engine, that is do not press a throttle pedal before an engine stop. If ignition is switched off not idling, not burned down fuel will get to (very hot) catalytic converter with possibility to its ignition and converter damages.
  6. Do not apply additives to fuel or impellent oil - they can contain the substances harmful to the catalytic converter.
  7. Do not maintain the car if because of hot oil in the engine there is an appreciable quantity of a dark blue smoke - not burned down carbonaceous sedimentation will cork channels of the converter and will reduce its efficiency; in certain cases the element will overheat.
  8. Remember that the catalytic converter works at very high temperatures, therefore, heat is reflected from a car floor - the casing becomes rather hot to ignite the materials which have stuck to it. Therefore, do not stop the car on a dry grass, on heaps of dry leaves and in a high grass.
  9. Remember that the catalytic converter fragile - do not strike on it with tools in operating time with final system. Be convinced that the converter is rather removed from jacks or other elevating mechanisms and do not drive the car on the rough road, potholes and other places where it is possible to hook the converter for the earth.
  10. In certain cases, in particular, when the car new and/or is used in start / стопном a mode, in the fulfilled gases there can be a sulfur smell (similar to a smell of rotten eggs). It often happens with the cars equipped with catalytic converters and occurs because of a small amount of sulfur in some brands of gasoline which enters reaction with hydrogen of the fulfilled gases with formation of hydrogen sulfide (H2S); - though this gas is toxic, it is developed not in such significant amounts to represent a problem. After the car will pass the first some thousand kilometers, the phenomenon should disappear - otherwise change a manner of driving or gasoline brand, it can solve a problem.
  11. The catalytic converter on well served and correctly maintained car will serve from 90 000 to 180 000 kilometers - then it is necessary to check regularly attentively level WITH to supervise overall performance of the converter. If the converter lost efficiency, it is necessary to replace it.

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8. Coupling