I had this exact problem with my last engine.  The repair is simple, the
No. 2 "Blue" temp sender has failed.  I've heard this is a common
problem.  The No. 2 temp sender is on the thermostat housing and costs
under $10.  The parts guy referred to it as the blue temp sender, it is
in fact blue.  Good luck with your new motor. BTW it may just be a
broken wire to the sender.  Oh, the reason it's ok for the first couple
min, and then when you restart it is because the ECU ignores the OXS and
temp senders for the first few min, this is the cold start cycle.

David Filcoff            dave@v-dub.musa.com
Volkswagens!            http://v-dub.musa.com
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87 Vanagon GL Wolfsburg Weekender (129k)
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