Adjustment Procedure

The MEMS idle control is an adaptive system and the ECM learns the engine load and wear characteristics over a period of time. The amount of stepper motor steps required to maintain the specified idle consequently will differ from model to model. In the event of a new ECM or an ECM from another vehicle being fitted, it will take a short period of normal driving for the ECM to learn the load and wear characteristics of that engine.

Adjustment Procedure

1 Switch the ignition on. 2 From the engine compartment, open the throttle disc on the throttle body fully. Because the throttle pedal switch contacts remain closed whilst the throttle disc is opened, the ECM recognises this as a command and indexes the stepper motor to 25 steps.

NOTE: If either the ignition is switched "off", or the engine cranked, the ECM will re-position the stepper motor to 180 steps.

3 Adjust the throttle cable to obtain an equal gap either side of the lost motion gap.

NOTE: In the event of the specified idle speed not being obtained after the engine has reached operating temperature, a tune procedure must be carried out using TestBook.