New Systems Overview

Group 00
Maintenance and
General Hints

Bulletin Number
00 03 92A (2126)

Woodcliff Lake, NJ
September, 1992
Product Engineering

SUBJECT:
Overview of New Systems for 1993 Model Year

MODELS:
All

For changes to Model Year 1993 refer to Table of Contents

With the introduction of the 740i/iL BMW presents its first production V8 engine in over thirty years.




The M60 engine is an aluminum alloy block V8 featuring four valves per cylinder and double overhead camshafts. A new engine management system (DME M3.3) is utilized to obtain smooth, powerful, and fuel efficient operation. A separate Technical Reference Information Bulletin, T.R.I. 11 02 92 (2124), describes the M60 engine in detail.




In keeping with the concept of the luxury performance sedan, output of the M60 engine is harnessed by means of a new electronically-controlled five-speed automatic transmission. Incorporating new designs to ensure extremely smooth shifts, low noise levels, and a high degree of reliability, the A5S 560Z transmission is controlled by a module which is in constant communication with the engine control module over a new data bus, the Controller Area Network (CAN) bus, further increasing shift refinement. The A5S 560Z transmission is filled with a special oil which requires no routine change intervals. A separate Technical Reference Information Bulletin, T.R.I. 24 01 92 (2127), describes this transmission in detail.




Because the M60 throttle is not controlled by electronic throttle control (EML), an additional control system is required for throttle closing during regulation by the slip control system (ASC+T). The new Automatic Throttle Valve System is designated ADS II and features an additional cable-operated, normally open "choke valve" ahead of the throttle. On command from the Slip Control Module (ASC+T), the Automatic Throttle Valve Control Module operates an actuator which closes the choke valve by means of a cable, thus limiting engine power. The ADS II system is described in detail in a separate Technical Reference Information Bulletin, T.R.I. 34 01 92 (2129).





The M50 engine has been further refined into a version known as M50TU ("Technical Update"). For 1993, the M50TU is installed in all E36 and E34 vehicles formerly equipped with the M50 engine. A variety of design modifications, including a new Engine Control System (DME 3.3.1) and the introduction of Variable Camshaft Control (VANOS), have resulted in improved torque curve, lower fuel emissions, better idle. quality, and lower fuel consumption, as compared to the M50 engine.

The M50TU engine is described in detail in a separate Technical Reference Information Bulletin, T.R.I. 11 03 92 (2125).

E36 vehicles equipped with the M42 engine will be available with an optional electronically-controlled automatic transmission (A4S 31OR) later during the model year.

All 1993 7 Series (E32) and 8 Series (E31) vehicles will be equipped with a passenger-side airbag. For further details, refer to T.R.I. 72 01 92 (2128).

All 1993 vehicles with automatic transmission will be equipped with a bowden-cable actuated interlock device which will prevent the removal of the key from the ignition switch unless the transmission is shifted into the Park position, and will prevent shifting from the Park position until the ignition key is turned to position 1 or 2 (accessory or run).

1993 7 Series (E32) and 5 Series (E34) will be equipped with mechanical seat belt tensioners on both front seats, similar in operation to those presently installed on 3 Series (E36) vehicles.





For Model Year 1993, vehicles are prewired for accessories as illustrated.

All 1993 Model Year vehicles have R-134a as refrigerant1 rather than R-12.
Please note that filling capacities for R-134a systems have been reduced
from R-12 levels. Refer to Technical Data Microfiche # 8, dated 5/92.

Several changes have taken place which are grouped by engine type:

- Oxygen Sensor Replacement Interval:

60,000 miles for M30, M42, M60 and M70 equipped vehicles

100,000 miles for M50TU equipped vehicles

(M20 equipped vehicles are still at a 50,000 mile interval)

- Service Interval Reminder

For 1993 Model Year vehicles equipped with M5OTU engine or M60 engine, the upper limit for service intervals has been increased to a maximum of 10,000 miles (same as 1992 E36 vehicles).

Unchanged from 1992 E32 specifications.

1993 850i vehicles with manual transmission are equipped with ASC+T (as opposed to ASC for 1992 850i with manual transmission).

1993 750iL vehicles will be equipped with a new low-beam system using Xenon gas-discharge lamps. The introduction of the 1993 750iL has been delayed, however, and this headlight system will consequently also be delayed A separate Technical Reference Information Bulletin will be issued to fully describe this system.