Engine - Will Not Start In Cold Weather

Group 11
Engine

Bulletin Number
11 08 94 (4139)

Woodcliff Lake, NJ
December 1995
Product Engineering

This Service Information bulletin supersedes S.I. 11 08 94 (4139) dated February 1995 which should be removed from your S.I. binder and discarded.

As a reminder, the information contained in this Service Information should be referred to if starting problems arise during the colder winter months ahead.

The [NEW] identifies changes made to this revision.

SUBJECT:
Engine Oil Viscosity Recommendations

MODELS:
All

Complaint:
Engine will not start during cold weather (32°F or lower).





Correction:
For reliable cold start performance it is imperative that the engine oil viscosity be matched to the ambient temperature range under which the vehicles will be operated. Please refer to the chart for recommended oil viscosities.

Note that BMW released "Special Oils," which all happen to be synthetic, will cover a much wider ambient temperature range than non "Special Oils." BMW approved "Special Oils" have gone through a dedicated BMW test procedure to determine their performance on BMW engines over extended ambient temperature ranges. Non "Special Oils" can be either mineral based or synthetic, but these oils have not been extensively tested over extended ambient temperature ranges in BMW engines.

The advantage of using the "Special Oils" over low viscosity non "Special Oils" is the tact that there is no need for an oil change once the ambient temperatures increase with warmer weather.

^ "Special Oils" currently approved by BMW are Mobile 1 SAE 5W-30 and Valvoline High Performance SAE 5W-30.

^ Verify that the proper DME update has been performed.

Refer to S.I. 12 08 94 (4117) for M50 non-VANOS
Refer to S.I. 12 07 94 (4116) for M50 with VANOS

[NEW] Refer to S.I. 12 09 94 (4132) and 12 06 95 (4258) for models with M60 engines.

^ Verify that the correct spark plugs are installed.

Refer to S.I. 12 03 85 (1085) for spark plug application.