Matt,

I had the same problem.....after much testing I found that the culpret was
the water temperature sensor.  I replaced the connection as well as a foot 
of the wire and have had no hesitation since.  But,  I still check for 
corrosion every other oil change.

By-the-way I have a pair of Eurovan jump seats for sale...$200.00 a piece,
never sat on.

John Grazul,  Rutgers University,  '83 Westy,  '92 Passat wagon