Attention! Gasoline is a flammable liquid, so when working with any element of the fuel system, take all fire safety measures. See the warnings at the beginning of paragraph 2.
1. Check up electric sockets, and also connections with weight. Unreliable connections are the main cause of problems in the control system.
2. Make sure. that the battery is fully charged, because at reduced voltage, neither the BEU nor the sensors will work reliably.
3. Check the air filter. A dirty or clogged filter can reduce engine power and economy.
4. Check the operation of the fuel pump (see paragraph 3). If the pump fuse is blown, replace it and check again. If the fuse is blown again, check the wiring to the pump for shorts to ground (see chapter 12 for wiring diagrams).
5. Check the vacuum hoses attached to the intake manifold for cracks, ruptures, or other damage causing vacuum to leak.
6. Disconnect the air duct from the throttle body and inspect the damper body for carbon deposits, deposits and dirt, especially around the damper. If there are any deposits in the damper body, determine the cause of their appearance by checking the operation of the gas recirculation and crankcase ventilation systems (see chapter 6).
7. Start the engine. Use a stethoscope to listen to each injector. Periodic clicks of the switched on electromagnet should be heard from the working nozzle (pic. 12.7). The click frequency should increase as the engine RPM increases. If there is no stethoscope. attach a long screwdriver to the nozzle of the horses and listen through the handle.
8. If the nozzle does not seem to be working (does not make clicks), take out a special injector tester and insert it into the injector connector.
Note. On the V6 engine, these devices cannot be used due to the peculiarities of installing nozzles. Start the engine and take a look. tester light flashes. If the light blinks, it means that pulses of sufficient amplitude are applied to the nozzle. If the tester light does not flash, further checks are necessary. They can be performed at the service station.
9. Stop the engine and disconnect from atomizers electric sockets. Measure the resistance of the electromagnets of all injectors with an ohmmeter. Compare your results with the values given in Technical Data. On a 4-cylinder engine, the resistance can be measured directly at the injector contacts. On a V-shaped engine, you need to measure at the pins of the connectors of the wiring harnesses going to the injectors (pic. 12.9). The connector pins correspond to the following injectors:
Right block:
- A, B - cylinder nozzle No. 1
- A, C - cylinder nozzle No. 5
- A, D - cylinder nozzle No. 3
Left block:
- D, C - cylinder nozzle No. 2
- D, B - cylinder nozzle No. 4
- D, A - cylinder nozzle No. 6
10. If the injector resistance does not match Technical Data, take it off (see paragraph 15) and measure the resistance of the injector and wiring separately to pinpoint exactly where the problem is (pic. 12.10).
11. Other checks of the control system are described in chapter 6.