AWD stalling at idle

[WytWun]

The ECU should be using the idle speed control valve to account for the load change of the A/C on/off. When was the last time the throttle body, and especially the ISC, was given a good clean? The ISC stepper motor coils can also be checked for resistance with a multimeter in case one of them has failed.

The idle air bleed screw should only ever be adjusted when the engine is fully warmed up and the ECU is forced into the correct adjustment mode - with J or later cars this requires a MUT unit or an Evoscan logging setup. In this ECU mode the screw should be adjusted so that the engine is idling at a target of 700rpm.