Frame
Control (only for multipoint injection)
1. A vacuum hose is located on top of the housing, connecting the housing to the fuel vapor accumulator. Disconnect it and put a pressure gauge in this place.
2. Start the engine and warm it up to operating temperature (fan should run twice). The pressure gauge should not show vacuum.
3 Slightly open the throttle valve, the pressure gauge should show a vacuum.
4. Stop the engine and check the adjustment of the cable and the smooth opening of the damper.
5. If the cable or damper is sticking, flush the damper shaft.
6. If flushing does not solve the problem, replace the housing.
Replacement
8. Disconnect the negative cable from the battery. Relieve the fuel pressure in the system (see section 2).
9. Remove air duct between air filter and throttle body (in case of two-point injection, remove the filter housing).
10. Tag and disconnect the vacuum hoses.
11. Disconnect the throttle cable (see Section 8) and, if installed, automatic transmission valve control cable (see Chapter 7B).
12. Disconnect the coolant passage hoses from the body (only for multipoint injection). In the case of two-point injection, disconnect the fuel hoses from the pressure regulator and throttle body.
13. Turn off four nuts of fastening and remove the case.
Pic. 13.13 Assembling the throttle body:
1 - body;
2 - gasket.
14. Installation is made in the return to removal order. Adjust throttle cable and automatic transmission valve cable (see Chapter 7B).
Throttle damper
Models from 1995 to 1997
15. The shock absorber slows down the closing of the damper.
Pic. 13.15 Throttle damper assembly
16. Slowly open the damper until. until the shock absorber bar extends to its maximum length.
17. Release the damper actuator lever and note the time until the lever touches the stop screw. This time should lie in the range of 0.25-2 sec.
- A) if the closing time is more than 2 sec. replace the damper control valve;
- b) if the shock absorber link does not extend, check for bending, leaks, or blockage in the vacuum hose. If there is no visible damage, replace the shock absorber.
Models since 1988
18. Start the engine and warm it up.
19. Connect the tachometer according to the manufacturer's instructions.
20. Disconnect the vacuum hose from the shock absorber and measure the engine speed. It should be in the range of 2000-3000 rpm.
21. If the speed is too high, adjust it by bending the lug on the damper lever.
Pic. 13.21 Adjusting the engine speed by bending the lug of the drive lever
22. If the engine speed does not change after disconnecting the vacuum hose, connect a pressure gauge and check for vacuum. If there is no vacuum, check the hose and replace if necessary.
23. If there is a vacuum, but the engine speed does not change, replace the shock absorber.
24. Adjust idle speed (see chapter 1).