I finally got to the bottom of this. The error lights were indicating a problem with the boost pressure control module, which is one of the four computers under the cover on the passenger side of the car under the hood, near the firewall.
It is the third module, the one with the hose running into it.
Cost for a new one from Alpina: $3100 US!
Fortunately Porsche used the same module in the 944 Turbo and Turbo S, part numbers 951.618.113.02 and 951.618.113.09 - either will work. These are available on eBay and I got one for about $250. I swapped the eprom with the one from my Alpina and voila, error message gone!
Members of the German forum alpina-forum.de were invaluable in troubleshooting this problem. You can read the full discussion here:
http://www.alpina-forum.de/forum/showthread.php?t=11623
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12-18-2016, 07:11 PM
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