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Cars with catalytic converter

Engines that We establish the C-Class are equipped with standard way catalyst. This catalyst requires that the gasoline engine was operated principally on unleaded fuel. Furthermore, vehicles with adjustable steering catalyst should be a carburetor.

Under controlled carburetor understood carburetor or fuel injection system, in which the fuel to air ratio can be continuously changed depending on driving modes and the oxygen content in the exhaust gases. This can not be done using a conventional carburetor, as it is not equipped with the corresponding control unit. For this reason, a return to the carburetor when the regulated electronically, or fuel injection system.

Carburetor receives commands from the oxygen sensor, which is installed in the exhaust pipe before the catalytic converter or exhaust manifold and is washed by the flow of exhaust gases. The oxygen sensor is a sensor and signal the residual oxygen content in the exhaust gases by means of voltage fluctuations and contributes to issue conclusions on the air-fuel ratio. In fractions of a second oxygen sensor may transmit corresponding electric signals to the control unit and the carburetor, thereby continuously changing the air-fuel ratio. This, on the one hand, is required, as in any case always changing operating conditions (idling, full throttle) and, on the other hand, also because only in this case, the catalyst occurs afterburning because exhaust gas engine still has a sufficient share of gasoline.

Therefore, to a temperature of 300 to 800 ?� C on the catalyst generally afterburning could occur, the fuel mixture should have a greater percentage of fuel than it would be required for clean combustion. Thus, when applying the catalyst to be reckoned with increased fuel consumption, reaching from one to five percent.

The catalyst installed under the base body of the car, instead of the additional muffler. The catalyst consists of a porous ceramic monolith coated with a layer of platinum or rhodium. To set the sensitivity to shock of the ceramic body, flexible and temperature-resistant metallic fabric.

In this case, we are talking about the so-called three-functional catalyst. This means that with this catalyst, based on the data obtained from the oxygen sensor, carry out the oxidation of carbon monoxide (CO) and hydrocarbons (HC) to CO _{2 and H 2 O,} and the simultaneous reduction of nitrogen oxides (NO _x) to nitrogen.

Caring for cars equipped with catalyst

To avoid damage to the oxygen sensor and the catalyst required to follow these guidelines:

- In principle, only refuel the car with unleaded petrol. If you have accidentally refueled with leaded petrol, the exhaust pipe must be replaced before the catalyst and catalyst. Before installing the new parts of the catalyst having to travel for at least two fuel tanks tucked unleaded gasoline. Starting the engine by means of pushing or towing can be carried out only when the engine is started immediately. Unburned fuel at ignition can lead to overheating of the catalyst and thus to its destruction. Use the start-up of the starter auxiliary battery.

- Avoid frequent, following successive cold start. In this case, the catalyst collected unburned fuel, which upon subsequent heating suddenly ignite, and wherein the catalyst is harmed.

- In case of difficulty in starting the engine should not be a long time to press the starter. During start-up fuel is injected continuously. Identify and correct the cause of the fault.

- Use only approved for operation of the spark plug company Mercedes.

- Do not check for spark discharge on the ends of the wires to the spark plugs.

- If there are interruptions sparking avoid high engine speed and immediately eliminate the defect.

- Do not park the car over dry leaves or grass. The exhaust system gets very hot in the catalyst zone and radiates residual heat even after stopping the engine.

- When filling or refilling engine oil especially pay attention to the fact that in any case not exceed the maximum mark on the dipstick. Otherwise the excess oil due to incomplete combustion, and reaches the catalyst noble metal may damage or completely destroy the catalyst.