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System of preheat of the diesel engine
When starting a cold engine ignition temperature is not achieved only through the compression, therefore, a pre-heating the air-fuel mixture. With this purpose in each combustion chamber glow plug is screwed. It consists of a body with a pressed-in heating element. When voltage is applied to rod heater winding for a few seconds warmed to a temperature above 850 ?� C, whereby the duration of heating to start rarely lasts longer than 10 s. When you turn off the instrument cluster warning lamp preheat engine can be started. To speed up the warm-up engine on models from 1987 model year pre-heating continues after its launch. The duration of heating is determined by the control unit depending on the coolant temperature. The control unit is located behind the center console under the duct. Information about the temperature of the engine is supplied to the control unit from the coolant temperature sensor. Based on these data the control unit determines the duration and strength of the current.
Checking the engine preheating When difficulties arise when the engine is started, first of all, measure the engine compression. If the compression is too low, then the ambient temperature is low the engine will not start up. Check glow plugs Remove the nut and disconnect the wire from the spark plug.
| Fig. 4.17. Use an ohmmeter to measure the resistance between the glow plug terminal and the cylinder block
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Connect in series to each glow plug ohm meter and check the resistance between the glow plug and the cylinder block (Fig. 4.17). If the resistance is not zero, the glow plug is defective and should be replaced.
| Fig. 4.18. Glow Plug: 1 - a nut and washers; 2 - wire connection; 3 - Candle
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Remove the faulty spark plugs. Screw the new svechunakalivaniya and tighten to 20 N ??? m (Fig. 4.18). Connect the glow plug wire and secure it with nuts and washers.
A WARNING Do not exceed the specified torque, as it can be damaged pin plugs and plug prematurely fail. Make sure that a candle bulbs do not fall oil or fuel. |
Glow plugs with charred heating rods.
| Fig. 4.19. Glow plug with charred core
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Burning rods glow (Fig. 4.19) is often the result of failure of the fuel injectors. Such injuries do not rank as an internal or external defects glow.
A WARNING If damage is found on and the engine is started badly, conduct an external inspection of the glow plug when the preheating. To do this, remove the fuel injectors and through holes watch glow plugs during heating. |
Upon detection of such glow is not enough to replace them. In this case, it is also necessary to check the fuel injectors on the injection pressure and tightness. Check glow plug relay
| Fig. 4.20. Connecting the glow plug relay to the battery terminals and check-circuit relay
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Remove the pin glow plug relay. Two additional wires to connect the relay to the battery terminals, as shown in Fig. 4.20, and check whether the relay contacts are closed. If the relay is not closed, replace the relay.
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