At 12:02 AM 1/8/2012, Mike Miller wrote:
>But...my temp gauge goes sl[e]wing up to the red zone and the light
>blinks.

Less common reason: short to ground in the temp sender wiring.

More common reason:  you have an old-style coolant-level controller
as found in roughly pre-'85 vans, and it has triggered.  Could be a
bad controller (and anyway you'd rather have the newer, cube-shaped
one which will cause the light to blink without visibly affecting the
needle), but more likely it's an open in the wiring of the level
sender (the plug comes to mind) or the sender itself which is just
two s/s pins sticking down into the pressure bottle.  Scrub the pins
with ScotchBrite, check/clean the connector, make sure the ground is
good.  If you're running a very weak coolant mix that could
conceivably cause this as well.

Sight unseen my bet is on the connector at the pressure bottle.

Yrs,
d