2.18.1. Check of idling and contents WITH

System of ignition and injection of Digifant (4-cylinder petrol engine)

1. Air filter
With the adjustable gate of heating of inlet air.
2. Inlet air duct
3. Shtekerny connection lambda probe and heating lambda probe
Installation site: on the console of hinged units, on the right in the direction of the movement.
4. Branch pipe of a butterfly valve
5. Potentiometer of a butterfly valve
6. The injecting valve
7. Fuel distributor
8. Fuel pressure regulator
9. Inlet collector
10. Idling stabilization valve
11. Stopper
In a measuring tube WITH.
12. The magnetic valve of 1 tank with absorbent carbon
(As additional equipment).
13. Vacuum pipeline
14. Digifant control unit
15. Transformer of high voltage (ignition coil)
16. The valve of cold start (to 5/93 g)
17. Ignition distributor
18. The thermostat of circulation of cooling liquid with the sensor of temperature of cooling liquid of the index of temperature
19. Sensor of temperature of cooling liquid
Blue, 2-polar Digifant.
20. Valve of adjustment of pressure of ventilation of a case of the engine
21. The screw of adjustment of turns of idling (to 5/93 g)
22. The sensor of temperature of the let-in air
With a potentiometer WITH and the screw of adjustment of contents WITH (to 5/93 g).


The 5-cylinder engine since January, 1993, and at the 4-cylinder engine since June, 1993 has no adjusting screws of idling and contents WITH.

Check of idling and contents WITH is made at the same time.

1. To interview memory, if necessary to eliminate malfunction. A survey of memory can be carried out only by the reading-out VW-1551 block. For this purpose the measuring block is connected by diagnostic plugs to two diagnostic nests in a box of safety locks.
2. To warm up the engine in the movement up to the temperature of oil not less than 80 °C.
3. To switch off everything electroconsumers. To switch off the conditioner.
4. To check the ignition moment (see subsection 2.14.5).
5. To check tightness of system of removal of the fulfilled gases.
6. To be convinced of operation of the valve of stabilization of idling. For this purpose to include ignition and to lay a hand to the valve. It has to vibrate and buzz. The valve is over a head of the block of cylinders near a branch pipe of a butterfly valve.


To connect control devices only at the switched-off ignition.

7. To connect the block for measurement of turnovers (tachometer) of the instruction. As a rule, the tachometer is connected to the plug 1 and the plug 15 of the coil of ignition.
8. To connect the block for measurement WITH to a measurement tube WITH in a motor compartment. The Zamerny tube is screwed on a final collector and, as a rule, closed by a light blue cap.


The hose of the measuring block has to sit densely. To watch that there was no leak of the fulfilled gases.

9. To disconnect a hose of ventilation of a case of the engine (1) from the valve of adjustment of pressure (2) and to arrange so that only clean air came to it.
10. To start the engine and to allow to work idling before the first turning on of the fan of a radiator. At the same time operation of the engine within about 4 min. with the increased speed is possible.
11. Then, on single turns to disconnect the plug from the sensor of temperature of cooling liquid (2-polar).


If the engine after removal of the plug, decays, then before restart to connect the plug to the sensor again. Otherwise the control unit will work in emergency operation and the correct check and adjustment will be impossible.

12. 4-cylinder engine: three times "to give gas", lifting at the same time turns slightly higher than 3000 rpm. Then to leave the engine to work at single turns.
13. To check turns of idling and to compare to the required value (see subsection 2.18.8).


During test adjusting works the fan of a radiator should not work.

14. To check contents WITH and to compare to the required value (see subsection 2.18.8).
15. On the cars released to 12/92 g or 5/93 g: if necessary to adjust turns of idling (screw) and contents ABOUT (screw B) alternate rotation of adjusting screws. Previously to remove a safety stopper of the screw of adjustment WITH (if is available). For this purpose to drill in a stopper an opening a drill of 2,5 mm, then to screw in the samorezny screw of 3 mm in an opening and to take out a stopper for the screw pincers. After adjustment to insert a new stopper.
16. To connect the plug of the sensor of temperature of cooling liquid.
17. To put on and fix by a collar a hose of ventilation of a case of the engine on the valve of adjustment of pressure.


If after that contents WITH increases, then it is not the result of faulty adjustment, and as a result of oiling from an engine case, owing to fluidifying of oil when driving in the busy city schedule.

18. After the bystry movement between settlements the content of fuel in oil decreases and contents WITH is again normalized. In short term it is normalized also after 30 min. the continuous movement or after oil replacement.
19. To disconnect measuring devices at the switched-off ignition.
20. To interview and erase record from memory. As a result of a plug detachment from the sensor of temperature of cooling liquid in memory malfunction "Was written down the sensor or conducting is faulty".