I'd say that either your wiring is bad or the sensor is going bad....  When
you unplug
the sensor you're probably jiggling it just enough to make it work enough to
start and run
for a while.

Steven

On Wed, Jul 21, 2010 at 10:04 PM, David White <sirgrumpsalot@gmail.com>wrote:

> My 87 vanagon won't start once the engine is warm. But if I unplug the
> coolant sensor and crank it a few times (it still won't start), then
> plug the sensor back in, the engine starts right up. Why and what's
> the fix?
>