The ZMZ-4062 engine does not have the usual idle system, like in a carburetor.

The function of the channels and the idle jet is performed by a microprocessor control unit using fuel injectors and an additional air regulator.

The regulator (РХХ-60 or 0280 140 545) is installed on the air intake system receiver.

It is an electric valve that regulates the air supply to the intake system bypassing the throttle valve, which ensures that the set idle speed is maintained at various engine operating modes (starting, warming up, engine braking, additional load from attachments).

In essence, this is an idle speed regulator.

If the regulator fails or there is a malfunction in its circuit, the control unit will turn on the KMSUD indicator lamp, and write the corresponding fault code into memory.

With a faulty regulator, the engine may stall at idle after starting and run at higher speeds.

If the butterfly valve sticks due to mechanical damage or contamination, the engine will idle unstably.

Checking the secondary air regulator

Turn off the ignition and remove the negative terminal from the battery.

Auxiliary air regulator checkAuxiliary air regulator test

With an awl or a thin screwdriver, we snap off the block clamp and disconnect the regulator connector.

We measure the resistance of the two windings of the regulator with an ohmmeter, for which we connect one probe of the device to the central terminal, and the other to the extreme ones in turn.

For a working regulator, the resistance of each winding should be in the range of 10-14 ohms.

Auxiliary air regulator checkAuxiliary air regulator test

Having removed the regulator from the engine, we put a piece of PVC tube on the central output and insert the end of the bare wire into it.

We connect the central terminal with the plus of the battery, the minus - alternately with the extreme ones.

In one case, the damper should open completely, in the other it should close

If it doesn't, shake the control slightly to make sure the damper is not sticking.

We replace the defective regulator.

Removing the secondary air regulator

Removing the secondary air regulatorRemoving the secondary air regulator

Loosen the clamp with a screwdriver

Remove the air supply hose.

Replacing the idle speed regulator ZMZ-406Replacing the idle speed regulator ZMZ-406

Loosen the lower hose clamp with a screwdriver.

Using a 10 key, we unscrew the two bolts securing the regulator to the intake system receiver.

Replacing the idle speed regulator ZMZ-406Replacing the idle speed regulator ZMZ-406

Remove the regulator assembly with the bracket by removing the lower branch pipe of the regulator from the hose

Remove the steel clamp and rubber tube from the regulator.

Install the regulator in reverse order

Replacing the idle speed regulator ZMZ-406

During installation, we are guided by the diameter of the regulator nozzles - the inlet is larger and should be located on top