The speed and timing sensor is located at the front of the engine on the right side

According to the sensor signal, the engine control unit determines the angular position of the crankshaft and its speed

According to the frequency of the signals generated by the sensor during the rotation of the synchronization disk mounted on the crankshaft pulley, the control unit determines the number of revolutions of the engine crankshaft, synchronizing the fuel supply by the injectors and the ignition timing with the engine's working process.

If the crankshaft position sensor fails, the engine will not start, since the control unit, without receiving a signal from the sensor, will not turn on the injection and ignition systems.

Disconnect the wire from the "negative" terminal of the battery.

Disconnect the 3rd sensor wire block located behind the engine intake pipe.

Replacing and checking the GAZ-2705 synchronization sensor

Remove bolt 2 and remove sensor 1.

Check the resistance of the sensor coil with an ohmmeter, it should be in the range of 850-900 ohms.

If the resistance value is not within the specified limits, replace the sensor.

Install the sensor in reverse order.

For normal operation of the sensor, the gap "a" between the sensor 1 and the synchronization disc 4 must be within 1.0-1.5 mm.

Timing Sensor Test

Turn off the ignition and disconnect the "negative" terminal of the battery.

Checking and replacing the ZMZ-406 synchronization sensor Checking and replacing the synchronization sensor ZMZ-406

Use a thin screwdriver or an awl to remove the spring clip of the shoe.

Disconnect the sync sensor connector.

Checking and replacing the ZMZ-406 synchronization sensor Checking and replacing the synchronization sensor ZMZ-406

Connect an ohmmeter to the central and one side output.

We measure the resistance of the sensor winding, which should be in the range of 700-900 Ohm.

Checking and replacing the ZMZ-406 timing sensor Checking and replacing the synchronization sensor ZMZ-406

To further check the health of the sensor, remove it from the engine.

You can verify that the sensor is working by connecting a voltmeter to its outputs

We quickly bring the metal rod to the core of the sensor - if it is working, voltage surges are observed on the device.

We replace the defective sensor.

Removing the timing sensor

Checking and installing the ZMZ engine phase sensor -406Checking and installing the ZMZ-406 engine phase sensor

Using the “10” key, we unscrew the bolt securing the sensor to the engine block

Remove the sensor from the hole.

Bending the sensor wire clamps located on the intake manifold and cylinder block, pull the wire down together with the connector

Install the sensor in reverse order.

After installing the sensor, we check the gap between its rod and the teeth of the synchronization disk using a set of probes.

The gap should be within 1-1.5 mm.