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 you lift the car.

General description

For decrease in release of not burned down hydrocarbons (NANOSECONDS), monocarbon monoxide (SO) and oxides of nitrogen (NOX) the cars of 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 pollutants stated above and oxygen in the fulfilled gases. Pollutants 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) for existence of cracks or damage. Make sure that all seagulls and turns are hardly tightened.
  2. Check the isolating cover (if is established) welded on the converter - it has to 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 leak of the fulfilled gases through converter flanges. Check existence of openings in cases of all converters.

Replacement of components


  1. Lift the car and install 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 against fastening.

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

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

Measures of precautions

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

  1. Do not apply ethylated gasoline on the car with the catalytic converter - lead will accumulate 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 the Head. In particular, do not forget to replace the filtering air cleaner element, the fuel filter (if it is established) and spark plugs in time. If воздушно / fuel mix too rich, then not burned down fuel gets to the catalytic converter, overheating an element and destroying the converter.
  3. If the engine misses flashes, do not use the car at all (or as little as possible), do not eliminate malfunction yet - the admission of flash leads to hit in the converter of not burned down fuel that leads to the overheat described above.
  4. You do not start the car towage or "from a push" - at the same time not burned down fuel which will cause an overheat after start of the engine will get to the catalytic converter - watch (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 an opportunity to its ignition and damages of the converter.
  6. Do not apply additives to fuel or motive oil - they may contain the substances harmful to the catalytic converter.
  7. Do not operate the car if because of hot oil in the engine there is a noticeable amount of 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 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 fragile - do not strike the catalytic converter it with tools in operating time with final system. Make sure that the converter is rather removed from jacks or other lifting mechanisms and you do not drive the car on the uneven 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 / the-foot mode, in the fulfilled gases the sulfur smell can appear (similar to a smell of rotten eggs). It often happens to the cars equipped with catalytic converters and happens because of a small amount of sulfur in some brands of gasoline which reacts with hydrogen of the fulfilled gases with formation of hydrogen sulfide (H2S); - though this gas is toxic, it is produced not in such significant amounts to represent a problem. After the car will pass the first several thousands of kilometers, the phenomenon has to disappear - otherwise change a manner of driving or brand of gasoline, it can solve a problem.
  11. The catalytic converter on well served and correctly operated car will serve from 90 000 to 180 000 kilometers - then it is necessary to check regularly attentively the SO level to control overall performance of the converter. If the converter lost efficiency, it should be replaced.