Do a search before posting. We talk about platinum plugs in E34 engines all the time and how they DON'T help things out.
There are a couple of things you need to do:
1) Pull the DME, remove the cover and see if any of the final stage resistors are burnt. Usually, the DME will actually smell burnt when this has occured. Running a leaking coil pack can blow one or more of them out, and you'll have a misfire no matter what you do.
2) Reset adaptations (do a search on the "Shogun Reset") after changing a component.
3) Get rid of the shitty plugs. Bosch F7LDCR (or the PRs are okay) dual electrode silvers or the BMW NGK plugs ONLY. And the dealer WILL give you the wrong plugs for the car, so specify NGK BKR6EK if that's how you buy parts.
4) Are you certain that the replacement MAF is the same? M50 ('91/'92 MY cars) have a different unit than the later M50TU cars.
best, whit
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