- difficult engine starting;
- unstable engine operation;
- engine stop at idle;
- increased crankshaft speed at idle;
- engine does not develop full power, insufficient engine response;
- jerks and dips in engine operation when the car is moving;
- increased fuel consumption;
- increased content of CO and CH in exhaust gases;
- glow ignition due to leaky injectors.
You will need an autotester.
1. Remove the fuel rail (see "Removing and installing the fuel rail").
Fig. 5.26. Fuel rail with injectors and fuel pressure pulsation compensator: 1 – fuel pressure pulsation compensator mounting bolts; 2 – fuel pressure pulsation compensator; 3 – fuel pressure pulsation compensator sealing rings; 4 – upper injector sealing rings; 5 – fuel rail; 6 – injector retainers; 7 – lower injector sealing rings; 8 – injectors
2. Remove injectors 8 (see Fig. 5.26) from the holes in fuel rail 5.
3. Check the resistance of the injector winding by connecting the autotester probes to the winding terminals. The resistance of a serviceable injector should be 12–13 Ohms. If the winding resistance is not within the norm, replace the injector, as it cannot be repaired.
USEFUL TIP: The injector's functionality can be checked with some degree of accuracy by supplying it with power from the battery using two pieces of insulated wire. When the wires are connected, a distinct click should be heard.
NOTE: Check the injector for the shape of the sprayed fuel torch and for leaks at specialized service stations, since such a check directly on the car is very fire hazardous. With some degree of accuracy, you can check the leaks of the injector by lowering its sprayer into a container with kerosene and supplying compressed air under a pressure of 3 bar to the nozzle. In a serviceable injector, air should not escape through the sprayer.
4. Each time the injectors are removed, be sure to replace the upper 4 (see Fig. 5.26) and lower 7 sealing rings.
5. If you are installing the old injectors, carefully wash their sprayers with solvent or carburetor cleaner.
WARNING: Do not wash the injectors by dipping them in cleaning solution to avoid damaging their electrical parts.
6. Install the injectors in the reverse order of removal. Before installing the injectors, lubricate the sealing rings with engine oil.
7. Install the injectors into the fuel rail and the rail onto the intake pipe, connect the pipeline to the rail, start the engine and check the tightness of the pipeline connection and the injector seals.