It would seem that what could be simpler than the design of the throttle assembly of an injection engine? A housing with a damper, and an idle sensor with an engine speed control mechanism operating at idle speed. And the fact that this very mechanism for controlling the idle speed of a running motor is nothing more than a stepper motor is a very narrow circle of motorists in the know.
Necessary
chemical cleaner for electrical contacts - 1 bottle
Instructions
Step 1
The principle of operation of the throttle assembly is as follows:
- the electrical signal from the throttle position sensor enters the electronic engine control unit, - the unit, which received a signal from the sensor, processes the information, and then sends an electrical impulse to the stepper motor;
- the stepper motor, reacting to the received impulse, activates the mechanism for changing the position of the throttle valve.
Step 2
Any failure in the idle speed setting system negatively affects the stability of the engine as a whole, expressed in engine interruptions that occur when shifting gears during acceleration or deceleration of the car. Difficulty starting or unstable operation of the motor in idle mode are also signs of a malfunction of the stepper motor of the throttle assembly.
Step 3
Driving practice has in its luggage a lot of cases when, after installing a new stepper motor in the throttle unit, nothing changed in the operation of the motor, and it was still “capricious”. Which led to bewilderment of unlucky car owners.
Step 4
As it turned out later, the reason for the interruptions in the engine idling was not the stepper motor, but the oxidized contacts in the block through which an electric voltage was supplied to it.
Step 5
In this regard, experts strongly recommend that car owners who decide to replace the device for changing the position of the throttle valve, first of all, inspect the condition of the contacts of the electrical block intended for connecting a stepper motor for oxidation and contamination.
And in cases of replacing the specified part with a new one, before connecting the electrical connector to it, clean and treat the contact groups with a special antioxidant chemical composition, which is sold in any car dealership. And only after that connect the stepper motor of the throttle unit.
