You mentioned that the timing is set to BTDC.  I don't know if VW changed
much from my '74 to your '79, but my bus has to have the timing set to 10
degrees AFTER top dead center.  There is some kind of funky vacuum
advance/retard system on the distributor that requires the idle timing to
be after TDC instead of before TDC, which is how most other cars are.

Just a though, hope it helps.

Craig

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Craig Standley				1974 Volkswagen Westfalia
University of Washington
Physics  				"Life is like riding the bus, it
cstand@u.washington.edu			 requires change." -Dennis Miller
http://weber.u.washington.edu/~cstand
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