Gasoline engines
1. Remove the upper engine cover (see subsection 2.1).
2. Disconnect the wiring harness from the throttle actuator.
3. Connect an ohmmeter to pins 3 and 5 of the drive and measure the resistance of the drive. The ohmmeter should show a resistance of 3-200 ohms. If the measured resistance is different from the specified value, replace the throttle actuator.
Attention! When installing a new throttle actuator, it must be coded to match it with the engine control unit, so it is recommended that the actuator be replaced at a workshop.
4. Check throttle actuator supply voltage. To do this, turn on the ignition and connect a voltmeter to pins 2 and 6 of the block with wires disconnected from the drive, and then to pin 2 and «mass» engine. In both cases, the voltage should be about 5 V. If the voltmeter shows 0, check the wires for an open or short circuit.
Diesel engine 1.9 l, 74 kW
1. Remove the upper engine cover (see subsection 2.1).
2. Start the engine and leave it to idle.
3. Switch off the ignition, at this point the throttle should close for about 3 seconds and then reopen.
4. If this does not happen, press the throttle actuator rod, it should move easily, without jamming.
5. Check the tightness of the vacuum hose on the throttle actuator fitting.
6. Check the operation of the throttle actuator by pumping air out of it, for example, with a hand vacuum pump.
7. If the throttle actuator is OK, check the throttle actuator valve. To do this, disconnect block 1 with wires from valve 2. Connect an ohmmeter 3 to the valve contacts and measure its resistance, it should be 25–45 ohms. If the measured resistance differs from the specified value, replace the valve.
8. If the valve is OK, check its power circuit. To do this, connect a 1 voltmeter to the terminals of the block and, having started the engine at idle, measure the voltage. The voltmeter should indicate battery voltage.
9. Turn off the ignition, after about 3 seconds the voltage should drop to 0. If this does not happen, check the wires for an open or short circuit. If no faults are found in the wiring, the engine control unit must be replaced.