What model year?

Google took me to this:

http://ww2.justanswer.com/uploads/normanahoyt/2012-02-03_151502_oil_pressure_switch.jpg

The Rialta uses a VR6 ?  Here's some images of oil pressure switches
on VR6 engines:

http://www.google.ca/search?q=vr6+oil+pressure+switch+image&hl=en&client=safari&pwst=1&rls=en&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=E1zCT-yzJoSoiQLcwsSiCA&ved=0CFgQsAQ&biw=1440&bih=786

Assuming the Rialta has two oil pressure switches, one will be a
"high" pressure oil switch.

On VW's using two oil pressure switches, the high pressure switch
kicks in when engine revved past 2K RPM. That said, on a Vanagon, this
will trigger a buzzer.

Maybe the wire to oil pressure sender got knocked loose?

Neil.

On Sun, May 27, 2012 at 8:41 AM, Hawk <vwnut@hawkcomputing.com> wrote:

> Got a visitor stuck in Minonk, IL. �Fixed coolant hose. �Now, oil pressure light on after revving engine.
>

-- 
Neil n

65 kb image Myford Ready For Assembly �http://tinyurl.com/64sx4rp

'88 Slate Blue Westy to be named.

'81 VanaJetta 2.0 "Jaco" �http://tubaneil.googlepages.com/

Vanagon VAG Gas I4/VR Swap Google Group:

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines