Idle Speed: Testing and Inspection

TESTING ELECTRONIC IDLE SPEED CONTROL







Switch off air conditioning or automatic climate control .

Selector lever in position "P" or "N".

Testers connect:
oil remote thermometer (018)
trigger clamp (011),
engine tester (026).

Vehicles up to 09/89 and model year 1990:
Connect test cable (034) to idle speed air valve (Y6).
2-pin: test cable 103 589 00 63 00
3-pin: test cable 102 589 14 63 00
Fit on ground clamp.
Connect lambda control tester (012).

Vehicles as of 09/89 and model year 1990:
Connect multimeter (003) to idle speed air valve (Y6) via test cable (033)102 589 04 63 00.

Position extraction device (014) at exhaust tail pipe.

Engine oil temperature approx. 80 °C.

Electronic idle speed control test (see table).
As of 09/89 and model year 1990: wait at least 28 seconds after start before measuring (heating speed).

Control range test at idle speed (see table).

Smooth engine running test by switching on all ancillary components.

Test And Adjustment Data:

Special Tools:

Commercially Avallable Testers:

a) Idle speed air valve with 3-pin connection



Note:

- If the specified value of a test step, e.g. step 4.0, is in order, it is not necessary to perform test step 4.1. Different component designations are possible depending on the wiring diagram or vehicles with optional equipment These designations are given in parentheses. This has no effect on the test (connections, specified value).

- Idle speed control is independent of the air flow sensor potentiometer.

- Engine speed increases when the coupling is disconnected from the decel fuel shutoff microswitch.

- Test TD signal if readout on tester fluctuates and engine surges.

Pest conditions:

- Intake system without leaks.

- Slide in idle speed air valve operates freely.

- Engine oil temperature approx. 80 °C.

- Coolant temperature sensor, decel fuel shutoff microswitch and idle speed detection throttle valve switch (RUF,KAT) in order.



Engine 102.983 Std.

Connect engine tester test cable (4) to test connection of idle air control valve X11/9.






1 Is not connected
2 Engine wiring harness
3 Test cable from set 201 589 00 99 00
4 Engine tester test cable
026 Engine tester
G1 Battery
X11/9 Idle air control valve test Connection






The idle air control valve test connection X11/9 is located on the right in the component compartment.

Key To Symbols:

Test Steps 1.0 - 1.3:

Test Steps 2.0 - 5.1: