Engine:
M88/3 (3.5L Inline-6), M30 (early 635CSi models before M6 designation)
Fuel System:
Bosch L-Jetronic fuel injection, fuel pump, injectors, pressure regulator, diagnosis
Ignition System:
Electronic ignition, coil, spark plugs, timing
Transmission:
Getrag 265 5-speed manual, ZF 4HP22 4-speed automatic (overhaul and service)
Drivetrain:
Rear-wheel drive, driveshaft, differential, axles
Suspension:
Front McPherson struts, rear semi-trailing arms, springs, dampers, bushings, alignment
Brakes:
Front and rear disc brakes, ABS (Anti-lock Braking System), hydraulic system, calipers, pads, rotors
Steering:
Power assisted steering system, steering rack, pump, fluid
Electrical System:
Wiring diagrams, battery, alternator, starter, fuses, relays, lighting, instrumentation, ECU diagnosis
Bodywork:
Exterior trim, bumpers, doors, hood, trunk, glass, chassis repair
HVAC:
Heating, ventilation, and air conditioning (if equipped)
Routine Maintenance:
Oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, belt inspection
Troubleshooting:
Diagnostic procedures for common and uncommon faults, symptom-based troubleshooting guides
Engine Repair:
Top-end overhaul, bottom-end rebuild, component replacement (pistons, rings, bearings, valves)
Transmission Repair:
Clutch replacement (manual), torque converter service (automatic), internal component repair
Brake System Repair:
Brake pad/shoe replacement, rotor turning/replacement, caliper overhaul, brake line replacement, ABS bleeding
Suspension And Steering Repair:
Component replacement (shocks, struts, ball joints, tie rods), power steering pump and rack repair
Electrical Troubleshooting:
Use of wiring diagrams, testing components, diagnosing electrical faults
Body And Interior Repair:
Panel alignment, door mechanism repair, glass replacement
Specifications And Data:
Torque values, clearances, fluid capacities, electrical values
Depth:
Comprehensive (covers basic maintenance to complete engine and transmission overhauls)
Diagnostics:
Detailed diagnostic procedures for engine management, fuel, and ignition systems
Rebuild Procedures:
Step-by-step instructions for engine and transmission rebuilds
Oil Change Interval:
Typically every 7,500-10,000 miles (12,000-16,000 km) or annually, refer to manual for exact schedule
Coolant Flush Interval:
Every 2-3 years or as recommended
Brake Fluid Flush Interval:
Every 2 years
Engine Oil Type:
API SG or higher, SAE 20W-50 or 15W-50 recommended (refer to manual for specific viscosity based on temperature)
Engine Oil Capacity:
6.5 liters (6.9 US quarts) with filter
Coolant Type:
BMW Blue or Green ethylene glycol based coolant
Transmission Fluid Manual:
API GL-4 or GL-5 gear oil, SAE 75W-90 or 80W-90
Transmission Fluid Automatic:
Dexron II or equivalent ATF
Differential Fluid:
API GL-5 gear oil, SAE 75W-90 or 80W-90 (check for Limited Slip Differential requirements)
Engine M88 M30 Notes:
Head gasket sealing, valve stem seals, timing chain guides, oil pump drive
Electrical Common Problems:
Fraying wire looms (especially engine harness), aging fuel pump relays, dashboard illumination issues
Suspension Wear Items:
Bushings (control arm, sway bar), ball joints, tie rod ends
Rust Prone Areas:
Fender arches, rocker panels, around windshield and rear window seals
