John;
If the wire between your gauge and the temp sender gets shorted to ground
, or if the coolant level sensor becomes disconnected,  you will get the
same symptoms. Since it should be pretty obvious if the level sensor is
un-hooked your problem is likely to be the temp sensor. That sender (on
our 85) is near the water pump/ thermostat. It has a single terminal
that looks like a nail head.  Locate it. Find the wire that should
attach to it, it is probably making contact  against the engine . If it
is attached disconnect it. Is the problem gone ? the sender is shorted.
Led still flashing?  Problem is upstream , look for a pinched wire. Let
me know.
Good Luck
ken lewis
kdlewis@ juno.com
86crewcab
85GL

On Sun, 13 Oct 1996 20:45:10 -0500 jmendoza@baynetworks.com (John
Mendoza) writes:
>Re: 84 Vanagon (gas engine)
>
>I just changed the coolant to a Prestone non-phosphate "looks like
>orange syrup" coolant.  It looked pretty appetizing ;-)
>
>Anyway, I think I broke something because when I started the engine, 
>the
>temperature indicator rose very quickly while the LED sensor blinked
>rapidly.  The temperature LED sensor has not yet stopped blinking, and
>the indicator is all the way to the right (MAX temp) even though the
>engine was cold.