BMW Z3 Repair Manual: Z3 Roadster, Z3 Coupe, M Roadster, M Coupe 1996-2002

• M44 engine with Bosch DME M5.2 (4-cyl.)
• M52 engine with Siemens DME MS 41.1 (6-cyl.)
• M52 TU engine with Siemens DME MS 42.1 (6-cyl.)
• M54 engine with Siemens DME MS 43.0 (6-cyl.)

• S52 engine with Siemens DME MS 41.1 (6-cyl.)
• S54 engine with Siemens DME MS S54 (6-cyl.)

• Getrag S5D 250 G
• ZF S5D 310 Z

• A4S 270 R
• A5S 360 R
• A5S 390 R

DIAGNOSTIC TESTING | CYLINDER COMPRESSION, CHECKING

A compression gauge is needed to make a compression test. For accurate testing, be sure that the battery and starter are capable of cranking the engine at least 300 rpm and that the engine is at normal operating temperature.

• Disable ignition system by removing DME main relay. See 610 Component Locations for relay location.



• Remove cylinder head top plastic cover.

4-CYLINDER MODEL: Slide special tool (see arrow) over spark plug wire. Use screwdriver for added leverage to pull straight up. Repeat for all cylinders.

NOTE: Special tool for spark plug connector removal is stored underneath cylinder head top plastic cover.

6-CYLINDER MODEL: Pull up on spring clip to disconnect ignition coil harness connector at each cylinder. Remove coil grounding straps. Remove coils.

CAUTION! Note location of all grounds. Failure to reinstall grounds can result in permanent damage to engine control module or ignition system components.

• Remove spark plugs from all cylinders.


NOTE: Check the spark plugs for oil deposits that may indicate poor cylinder sealing, then set them aside in order. Re-install used spark plugs in the same cylinders from which they were removed.


• Install compression gauge in first cylinder spark plug hole, tight enough to form a good seal.



• With parking brake set, transmission in PARK or NEUTRAL, and accelerator pedal pressed to floor, crank engine with starter. Record highest value indicated by gauge.

FRONT WHEEL BEARINGS

The front wheel bearings are permanently sealed and require no maintenance. The bearing is integral with the wheel hub and pressed onto the steering arm stub axle.

Special press tools are required to replace the front wheel bearings. Read the procedure through before beginning the job.


FRONT WHEEL BEARING | REPLACING

1. Raise car and remove wheel.


WARNING! Make sure car is stable and well supported at all times. Use a professional automotive lift or jack stands designed for the purpose. A floor jack is not adequate support.


2. Pry off dust cap from center of wheel hub. Bend back staked part (see arrow) of wheel hub (axle) collar nut.



3. Remount wheel and lug bolts. Lower car to ground to gain leverage in loosening collar nut.



4. Loosen collar nut. Do not remove nut completely.

• General Data and Maintenance
• Engine
• Transmission
• Suspension, Steering and Brakes
• Body
• Body Equipment
• Electrical System
• Equipment and Accessories
• ELE Electrical Wiring Diagrams
• OBD On-Board Diagnostics