Mercedes of the S-class W202

1993-2000 of release

Repair and operation of the car



Mercedes W202
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Lubrication system
+ 5. Cooling system
+ 6. Heating, ventilation
+ 7. System of ignition
- 8. Fuel system
   + 8.1.1. Introduction
   - 8.2. System of injection of petrol engines
      8.2.1.1. Principle of work of PMS
      8.2.1.2. Principle of work of HFM
      8.2.2. Self-diagnosing of a condition of system of ignition and injection of fuel
      8.2.3. Air flowmeter
      8.2.4. Thermal sensor of cooling liquid
      8.2.5. The sensor of the soaked-up air
      8.2.6. System of vacuum pipelines
      8.2.7. The fuel distributor with valvate nozzles
      8.2.8. Valvate nozzles
      8.2.9. Oxygen sensor (lambda probe)
      8.2.10. Diagnostics of malfunctions of system of injection of gasoline
      8.2.11. What should be known to the owner of the car with the injector engine
      8.2.12. Turbo doctor
   + 8.3. System of injection and power supply of diesel engines
   + 8.4. System of production of exhaust gases
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries




8.2.11. What should be known to the owner of the car with the injector engine

GENERAL INFORMATION

Injector motors surpass carburetor in many parameters, to take at least their profitability and trouble-free start in a frost. Nevertheless, carburetor under our conditions sometimes are more advantageous. And even some car makers deliver on our market cars with such engines. It is all about quality of gasoline which is sold at us.

The injector engine is calculated on high-grade gasoline which at our gas stations you will find not often. Besides, different systems of injection have the specific features, they need to be considered at operation of the car. And in our market there is a lot of such systems: with mechanical injection "To (KE) - Jetronic", electromechanical "L-Jetronic" and electronic: "Motronic", "Lucas", "Marelli".

Many systems have two operating modes: the main and emergency: at malfunction of one of sensors. The driver can not notice such malfunction: on the dashboard there is no alarm signal, and the engine continues to work (but not in the optimum mode any more). Similar quite often happens in "Audi-80" to the central injection. About a third of the motorists having such cars do not even guess that they go in emergency operation. And it leads to the increased fuel consumption, power deceleration, uneven operation of the engine and the complicated start-up. Malfunction comes to light only during the next servicing. Therefore it is worth dwelling upon the "weak" places of each system which are shown under our conditions.

Systems with mechanical injection. They more than others, are subject to physical wear. The regulator of pressure of fuel fails usually through 80–120 thousand km of a run (start of the engine considerably worsens), nozzles: through 60–80 thousand (uneven operation of the motor, the increased fuel consumption). The refusal of nozzles is especially artful as not at once you will notice it. Diagnosing and repair require the special equipment.

Sore point of systems with electromechanical injection: an air suction through the numerous vacuum hoses tending to cracking after 4–5 years of service. In particular on BMW and, in a little smaller degree, on "Audi". To reveal such defect quite difficult.

At electronic systems: the problems. For example, the accumulator "sat down", and you on an old habit decided "to light" from other car. As a result the electronic block fails. And use of ethylated gasoline will be put, in turn, out of commission by a lambda probe and the catalyst.

In general, both mechanical, and electronic systems of injection have the pluses and minuses. At mechanical the thicket is refused by gasoline pumps and batchers distributors. At electronic the gasoline pump is more durable and is cheaper, but any malfunction of the computer will cost much. Besides, we, alas, have more reasons for failure of any system, than in Western Europe or America: low-quality gasoline, dirt on roads and chemicals with which they are strewed. Therefore it is worth listening to recommendations of experts. Try to use import gasoline if there is such opportunity; for removal of moisture from fuel-supply lines during each filling fill in special medicine in a tank; through each 10–15 thousand km of a run do full washing of system of injection.

One more feature: any failure fixes the computer. And even after replacement of a faulty detail it will issue incorrect commands: until not to erase" failure at the special stand.