Yeah, when you close the butterfly in the final video and the smoke turns dark brown, that is what was happening in the video just before. It proves your butterfly is not operating correctly in some circumstances. I think there are probably multiple problems combining here.
Personally, I don't know enough about that butterfly system to give any helpful advice except that I might try wiring that butterfly open all the time and see what happens.

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1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
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