Idle Speed/Throttle Actuator - Electronic: Service and Repair

Replacing idle speed control valve (M52TU, M54)

Turn off ignition.
Follow instructions for disconnecting and connecting battery. Disconnect battery negative lead.







M52TU only:
Remove intake filter housing.
Pull Bowden cable upwards out of holder (1) and suspend from throttle.







Release hose clamps (1).
Detach intake hose piece from throttle assembly and idle-speed control valve.







Installation:
To facilitate installation, fit air-mass flow sensor with intake hose (1). Coat intake hose (1) with antiseize agent.


M54 only:
Remove intake hose completely (between intake filter housing and throttle assembly).


M52TU and M54:







Disconnect following plug connections:
1 - Resonance flap
2 - Idle-speed control valve


Installation location:







Idle actuator (2) is fitted below intake air manifold, directly above throttle (1).







Release screw (1) on cable duct mounting.
Release screws (2) on holder of idle actuator (3).
Remove idle actuator valve with holder from intake air manifold.







Detach idle actuator (2) from rubber retainer (4).
Always replace gasket (1) from idle actuator (2) to intake air manifold. However, during reinstallation, do not fit gasket on idle actuator but install first in intake air manifold.


Installation:







Replace gasket (1). To facilitate installation of idle actuator, coat inside of gasket with antiseize agent.

NOTE:
Interrogate fault memory of DME control module.
Check stored fault messages.
Rectify faults.
Then clear fault memory.