Your symptoms could be caused by a mechanical fuel pump in the early stages of failure or intermittent problems with the fuel pump relay in the case of an electric fuel pump. I'm not sure what type of fuel pump the +8 used in the 80's but it might be something else to think about.
1994 +8, BMW Calypso Red.
2002 4/4, 4 seater, BMW Calypso Red.
How do you open the boot?
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