John Doe, this is not a big deal when you lose only a small amount of coolant.
First, you need to top up the coolant reservoir (LHS) - not to be confused with
the expansion tan (CENTER behind license plate). You disconnect the hose from
the cap, remove the cap, fill with antifreeze mixture to the very top, replace
the cap, refasten the hose to the cap.
Next you need to fill the expansion tank up to the MAX level. Now when you
drive, the coolant light should be OFF. If it comes ON again, let the engine
cool down overnight and repeat the entire process in the morning
In any case, keep an eye on the expansion tank level and keep topping up to the
MAX level.
Eventually, the system will purge itself of any air.
-Larry
'86 Syncro Westfalia

John Doe wrote:

> After several suggestions from some members, I went ahead and purchased a
> new temp coolant sensor and o-ring and headed under the van as soon as I got
> home.  Looked pretty straightforward - disconnect sensor, 1 clip and out it
> would come.  WRONG!  I pulled the sensor and soon found my arm soaked in
> "blue koolaid". <snip>
> Now I have a coolant problem right?  I read my items about air in the
> cooling system that can cause overheating.  I probably lost about 1/2 quart
> in my adventure.  So what do I do now?