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Service fuel injection system
Most of the work related to the repair and maintenance of the injection system must be carried out by experts in the workshop. There are available the necessary diagnostic devices and related equipment. When a fault in the electronic control it is sometimes necessary to carry out a number of specialized tests to discover the cause of the fault. The only way to determine the damage to the relevant units and parts and to avoid more expensive repairs. Self-control is possible defect that occurs in violation of the control unit, the status of sensors, switches and cabling.
1. Check if the fuse is, whether connected to the relay connectors and spigots. 2. Make sure that the heating system is working properly. 3. Check the fuel supply system. 4. Perform a visual inspection of the injection system.
| Fig. 4.79. Diagnostic Control Unit
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5. If that does not help, turn the control unit to check and control memory.
PRACTICAL ADVICE From the viewpoint of diagnosis control unit depends on the engine operating condition. When driving in the drive memory error are taken, at a stop, and the battery is disconnected, they are removed. EDS control system equipped with an additional source for the system memory, it provides entry into the memory even small faults occurring in a short time. By comparison, in the main memory only those defects which must be removed immediately. Minor faults that occur very rarely, the memory is erased. "Read" of these errors may Mercedes station via a special tester (HHT) (Fig. 4.79). There is also a set of other characteristics and tests. |
Visual inspection of the fuel injection system "15,000 km" 1. Check for leaks air hoses. 2. Check the fit and condition of the brake booster vacuum hose. 3. Check the crankcase ventilation hoses. 4. Check the fuel lines for leaks and proper connection of the fuel because the fuel. 5. Check all electrical connectors and reliability of their connections in the wiring of the injection.
Faults of engine shutdown If the system is faulty or de-energized, the motor turns off. On the failure of the system also indicates that the engine does not start at a working injection system and a sufficient amount of fuel.
"15,000 km" 1. Check the connection and the wire itself to the system shut down. 2. When the ignition key is in the vicinity of the node is turned off, you should hear a click. 3. If it does not click, it shows a power failure or the system itself. 4. Turn on the ignition and check the voltage on the connector system. 5. If there is no voltage, defective cable or loose fuse installed. 6. If the voltage is - may be a fault of the system itself off.
Control of the air connections for leaks With a loose connection in the intake system enters a so-called outside air or conversely, of a pumping system of the air discharged to the atmosphere. This leads to disruption of the estimated mode, and therefore incorrect dosing injection. On leakage compounds usually indicates motor operation is intermittent.
"15,000 km" 1. Check for cuts and injuries, as well as planting density vacuum hoses connected to the intake manifold and the injection system. 2. Warm up the engine and let it run at idle. 3. From the spray-spray sprinkle fuel suction system flanges, gaskets of suction channels and pipelines vacuum lines. If these compounds when sprayed the engine speed changes, this connection is leaking.
Faults nozzles The engine works hard, I heard the noise of bearings, ringing sound of the muffler from time to time there is a exhaust gray smoke. With such signs must be sequentially disconnected one by one pipeline leading to the nozzles. If one of the disconnecting pipelines are no changes in the motor, this expectation is not working nozzle. Disclaimer nozzles can be caused by pollution. After a long car parking needle injector may "become attached" to the body. With long operation the nozzles of the injection pressure is reduced. At station there is a special device that determines the suitability of the nozzle. If the injector starts operating at a pressure below 100 bar, it must be replaced.
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