Fuel system is pressurised: Reduce fuel pressure with Pressure Tester KM-J-34730-91 via testing port - collect escaping fuel in suitable container - observe safety regulations and national legislation.
Depressurise cooling system by opening of closure cap on coolant compensation tank.
Remove, Disconnect
Remove coolant hoses from coolant compensation tank and remove coolant compensation tank. Collect escaping coolant.
Unscrew fuel return line (1, see illus. I) from fuel pressure regulator and lay aside. Detach wiring harness plug from idle speed stepper motor.
Detach fastening bolts (2, see illus. II) and remove idle speed stepper motor carefully from throttle body. For clearer representation, the idle speed stepper motor is shown with the throttle valve body removed.
Install, Connect
Install idle speed stepper motor with new seal ring. 1) .
Important!
To prevent damage to housing and idle speed stepper motor during installation, the gap (see illus. I) between piston and flange must not be greater than 33 mm. In case of deviation, carefully press in piston.
Install, Connect
Connect wiring harness plug to idle speed stepper motor. Install fuel return line (1, see illus. II) to fuel pressure regulator.
Mount coolant hoses on coolant compensation tank and install coolant compensation tank.
Top up and bleed cooling system - see corresponding operation. Ensure that anti-freeze is adequate down to -30 ° C / -22 ° F.
1) Bolts must be re-cut before recycling and inserted after being coated with bolt locking compound (red). Installation time max. 10 min.
Important! 
Remove, Disconnect 
Install, Connect 