Idling-speed problems SI 0633 En (Supersedes Edition 11.1998)
Vehicles with Motronic M 1.5.5:
* Alfa Romeo 156 1.8i 16V TS Engine AR 32.201 Control unit 0 261 204 732
* Alfa Romeo 156 2.0i 16V TS Engine AR 32.301 Control unit 0 261 204 270
IDLING-SPEED PROBLEMS
Engine running problems may be encountered at idling speed on the above-mentioned vehicles.
In cercases, the engine may also be in limp-home mode.
Possible customer complaints:
* Fault lamp lit
* Idling speed too high
* Engine cuts out for no apparent reason
* Engine hunts at idle
* Engine not revved to more than 1500 1/min (speed governing)
Engine in limp-home mode
Cause:
Over-frequent movement of idle actuator at same position in control mode.
This leads to an insulating layer (contact resistance) on the commutator
and the idle actuator can thus no longer be effectively activated.
Remedy:
The engine running problem can only be rectified at a Fiat/Alfa Romeo workshop.
This is a warranty situation involving renewal of the idle actuator
and provision of optimized software for the Motronic control unit.
The current idle actuator and optimized software can be recognized as follows:
* All current idle actuators as of date of manufacture FD 864 are
marked with a green dot.
* All control units marked on the rating plate with development no. 066
or higher are programmed with the optimized software.
This only applies to the control units
0 261 203 732 for 1.8 l and
0 261 204 270 for 2.0 l engine.
Conversion is no longer necessary given compliance with the following two items:
* Green dot on idle actuator as of
date of manufacture FD 864.
* Development no. 066 or higher
(on rating plate of Motronic
control unit).