Idle speed and fuel mixture adjustment
1. See Chapter 1.
Checking the fast idle system
11.2a Inspect the fast idle diaphragm hose (1) for cracks and signs of wear - disconnect the hose before checking the diaphragm; unscrew the two screws (2) to remove the diaphragm; adjusting screw is used to adjust the diaphragm (3)
11.2b Inspect the hoses and wires connected to the diaphragm of the fast idle system (1) - unscrew the two screws (2) and remove the solenoid mounting bracket
2. Check the vacuum hoses and fast idle solenoid wires (11.2a and 11.2b).
3. Connect a vacuum pump to the fast idle system diaphragm. Connect a tachometer. Start the engine and leave it to idle.
4. Using the pump, create a vacuum of 295 mmHg. The vacuum should increase. If not, replace diaphragm.
Replacing and adjusting the diaphragm of the fast idle system, which increases the engine speed when the electrical equipment or the hydraulic power steering system is turned on
Replacement
11.9 Retract the stem in the direction of the arrow and disconnect the diaphragm stem from the lever
9. Disconnect the throttle lever return spring. Loosen the two fixing screws (11.2a), disconnect the diaphragm rod from the release lever (11.9) and remove the diaphragm.
10. Install a new diaphragm and connect the vacuum hose.
Adjustment
11. Check and adjust idle speed.
12. Remove the solenoid mounting bracket (11.26). Disconnect the connector and connect the solenoid directly to the battery.
" 13. Slightly open the throttle and increase the engine speed to 2000 rpm, then slowly close it.
14. Check the engine speed and adjust it by turning the adjusting screw (11.2a).
15. Repeat the operations described in point 13 and check the engine speed again.
Adjusting the diaphragm that increases the engine speed when the air conditioner is turned on
11.16 To adjust the engine speed in fast idle mode when the air conditioner is turned on, tighten the throttle adjusting screw (indicated by an arrow)
16. Start the engine and turn on the air conditioner. The solenoid valve should open and the intake manifold vacuum should open the diaphragm. Check the engine speed in this mode and adjust it, if necessary, by tightening the adjusting screw (11.16).
Checking the solenoid valve for the fast idle system
17. Turn off the ignition. Remove the solenoid valve and disconnect the connection connector (11.2b).
18. Check the resistance of the solenoid coil and replace the valve if necessary.
Checking the fuel shutoff valve, enrichment valve, mixture control valve, and float chamber vent valve
11.19a To check the windings of the solenoid valve, disconnect the connection connector and measure the resistance between the indicated terminals (for the float chamber vent valve, measure the resistance between the specified terminal and the negative battery terminal) and compare the obtained values with the values given in the technical data section:
1. Solenoid valve for adjusting the composition of the mixture; 2. Enrichment valve; 3. Fuel cut-off valve; 4. Float chamber vent valve
11.19b Location of the fuel cut-off valve
11.19c Enrichment valve location
11.19g Location of the mixture control solenoid valve
11.19e When replacing the solenoid valve, remove the terminal (1) on the reverse side of the connection connector by pressing on the tab located near the terminal with a screwdriver. To remove the float chamber ventilation solenoid valve (2) unscrew the three fixing screws
19. Disconnect the connection connector. Check the resistance of the solenoids windings and replace them if necessary (11.19a, 11.19b, 11.19c, 11.19d and 11.19e).
Checking and adjusting the throttle position sensor
Examination
11.20 To test the throttle position sensor, disconnect the connector and measure the resistance between terminals 2 and 3
20. Check the resistance between terminals 2 and 3 of the sensor and check that the resistance gradually changes when the throttle is opened (11.20).
Adjustment
11.21 Check that the fast idle cam is free (the lever must not rest against the cam)
1. Fast idle cam; 2. Lever
21. Warm up the engine. Loosen the accelerator cable and check that the fast idle cam is free (11.21). Stop the engine.
11.22 Loosen adjusting screws SAS-1 and SAS-2 until the throttle valve is fully closed while counting the number of revolutions
22. Counting the number of revolutions, unscrew the adjusting screws for engine speed (SAS-1 and SAS-2) (11.22), so that the throttle valve is fully closed.
11.23a If this type of throttle position sensor is installed on your car (1), use the screw to adjust it (2).
11.23b If this type of throttle position sensor is installed on your car, unscrew the fixing screws and adjust the sensor by turning it
1. Throttle position sensor
23. Check the voltage of the sensor with the ignition on between terminals 2 and 3 and adjust it if necessary by turning the adjusting screw or by turning the sensor itself (11.20, 11.23a and 11.23b).
24. Turn off the ignition.
25. Screw in the adjusting screws SAS-1 and SAS-2 the same number of turns as they were unscrewed.
26. Adjust the tension of the accelerator cable. Start the engine and check the idle speed.
Checking and adjusting the carburetor damper
27. Warm up the engine and turn off all electrical equipment.
11.28 With the engine idling, open the throttle until the lever touches the SAS-3 screw
1. Damper; 2. Stock; 3. SAS-3; 4. Lever; 5. SAS-2
28. Fully open the throttle until the stem touches the SAS-3 screw (11.28).
11.29 Close the throttle until the SAS-2 screw touches the lever and check the engine speed
29. Close the throttle until the SAS-2 screw touches the lever (11.29) and check idle speed.
30. If the speed is not as specified, adjust the damper by turning the SAS-3 screw.
31. Pull the lever back and check that the engine speed slowly returns to idle speed.
Checking the air damper
11.32 Check that the marks on the volute body and the shutter match
1. Bimetallic spiral; 2. Marks
32. Check that the marks on the damper body and the bimetallic spiral coincide (11.32).
33. When the engine is cold, depress the accelerator pedal, the choke should be fully closed.
34. Check that when starting the engine, the damper opens slightly by 1.5 mm. If not, check the bimetal coil, choke diaphragms and vacuum hoses.
Checking and adjusting fast idle
11.35 Disconnect the vacuum hose from the choke opening diaphragm
1. Air damper opening diaphragm
35. Warm up the engine and turn off all vehicle electrical equipment. Remove the air filter. Disconnect the vacuum hose from the choke opening diaphragm (11.35).
11.36a Install the lever (1) on the second tooth of the fast idle cam (2)
36. Install the lever on the second prong of the fast idle cam. Start the engine and adjust the engine speed if necessary by turning the fast idle adjusting screw (11.36a).
11.36b Adjust the fast idle speed by turning the adjusting screw (indicated by an arrow) and 11.36b).
Checking the bimetallic spiral
11.37 To check the bimetallic coil, disconnect the connector and check its resistance with an ohmmeter
1. Spiral connector; 2. Float chamber cover
37. Check coil resistance. It should be 6 ohms at room temperature. If not, replace coil (11.37).