I recently puchresed a 1991 BMW 318 IS and im suspecting it is a 1.4 or a 1.8L DOCH not positive But above my fuse box there is a hub(Little Black box)that looks like it hold a two prong relay or other device all i know is that my car wont start without it and i am unaware of what the part is all repaair manuals iv purchresed are unspecified.
This is a question for your BMW dealer. Call them up with the VIN, using the 8th digit they will be able to decode what engine you have, and tell you more specifically what that switch or relay does.
If can hes right but if u search around for TIS,ETK tht healp u also in long run
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