Table of contents: Checking the work ↓ Checking the adjustment ↓
Caution: With the ignition off, disconnect the plug on the control valve.
Checking the work
Turn off the ignition and check the control valve for vibration.
If it is not present, check the voltage supply as follows.
Disconnect the plug on the control valve and connect a voltmeter to the central contact of the plug and to ground.
Nominal value: 12V - battery voltage.
Measure the voltage between the central and outer contacts. The required value is 1-2 V less than the battery voltage (10 V).
Measure the resistance between the central and outer contacts of the valve with an ohmmeter. The required value is 3-8 Ohms.
Checking the adjustment
Check conditions: Idle speed adjustment should be normal.
Warm up the engine. Oil temperature 80°C.
With the ignition off, connect the tachometer and the device for measuring the averaging coefficient.
Turn off all electrical consumers, including the air conditioner.
Start the engine and let it idle.
Take the value of the averaging coefficient and write it down.
Clamp the idle speed control hose with pliers. The averaging factor should increase.
Release the hose and the averaging coefficient should drop.
Cars with air conditioning: Turn on the air conditioning, the speed should increase by 100 rpm. Otherwise check the KE-Jetronic control unit, otherwise replace (is done in the workshop).
(This publication is borrowed from the resource: «AudiManual.ru»)