Audi 100/A6

1990-1997 of release

Repair and car operation

14.11.3. Enemies of the catalyst

THE GENERAL DATA

Except physical destruction there is one more frequent reason of failure of the catalyst. Fuel. It is extremely sensitive to fuel structure. If gasoline этилированный тетраэтил the lead, containing in it, it is postponed on an active surface каталитического "brick" and quickly "salts" it from what any reactions stop., Apparently, on refuellings and tips of hoses began to put the different size, and distributing columns paint in different colours, and write about it at every turn, and all the same consumers sometimes confuse and fill in not that gasoline. And after all it is enough to "burn" half-tank of such gasoline, and the catalyst will be lost irrevocably.

But not only этилированный gasoline – the enemy of the catalyst. The catalyst can be ruined and неэтилированным if the control system of the engine is faulty, short burns down a mix or the engine it is worn strongly out.

Threefold каталитические neutralizers ("threefold" because as the catalyst set of three precious metals serves) establish only on those cars which engines are equipped by the closed monitoring system of an exhaust. In front of the catalyst the oxygen gauge which traces structure of an exhaust is established and transfers this data in the central processor. Depending on the oxygen maintenance in an exhaust, БЭУ regulates structure of a gas mixture and ignition so that their optimum values were supported. It serves as the main protection for the catalyst, and also provides economy of fuel and an engine overall performance. The catalyst does not transfer the big deviations as a part of a working mix. Badly adjusted engine with the raised maintenance of hydrocarbons in an exhaust simply ruin the catalyst. If the mix too poor, it can cause a sharp overheat of the catalyst from what the monolith, only already "physically" again will suffer. Thus, catalyst "life" depends on serviceability of a control system of the engine.

Much depends and on serviceability of the most oxygen gauge. With "age" it becomes "lazy" or absolutely fails that affects structure of a mix and, accordingly, on serviceability of the catalyst.

Spoil the catalyst the exhaust of strongly worn out engine churning butter can also. It, getting together with an exhaust to the catalyst, "is baked" on a monolith surface, like a varnish, and does not allow to the catalyst to work.

There are also other harmful factors. For example – candles. Improper candles will not give full combustion that can cause in the catalyst pernicious reaction of fusion ".

Be very cautious in application of additives to gasoline or oil. The majority does not reflect on it, and after all additives too can influence the catalyst harmfully. If on a product it is not written: "it is compatible to the catalyst", do not risk better.

One more dangerous case – start of the engine by towage. Thus there can be a hit in the catalyst of simply pure gasoline. It, first, poisons the catalyst, but also can cause instant reaction and even explosion. Look also where go – try not to get to deep pools. The working temperature of the catalyst makes an order 900 ° S.Vnezapnoe its hit in water can be fatal.

As a whole, it is noticed that catalyst service life is influenced by service conditions. Catalysts by the cars maintained in city conditions when the engine often get more suffer. On the other hand, at long high-speed driving on highways the catalyst also spoils that overheats ".

At last, you arrive reasonably if begin to examine regularly all system of an exhaust. If arms are broken or rubber suspension brackets have fallen off, the exhaust pipe will vibrate, transferring to the catalyst unnecessary loadings.