Your electronics were soaked.
Use electrical connector cleaner and dielectric grease on all connection points.
Hand washing is a much better option.
The high pressure water will do this to the electronics and get right into the seams of the body panels, not good.

dylan

________________________________
From: Michael Sullivan <sandwichhead@GMAIL.COM>
To: vanagon@GERRY.VANAGON.COM
Sent: Monday, April 6, 2009 12:34:19 PM
Subject: Loss of Power after carwash

First... I have not finished diagnosing this, but wanted to put it out
there.� I got back from the beach on Sat and ran the van through an
under-carriage rinse yesterday.� Immediately noticed a loss of power, about
40-50%.� If i put it in low(auto) then I eventually get it to run better,
but as soon as I switch to a higher gear, seems I lose it again.� Left it
overnite and took it on a 5-6 miles hwy drive to 'dry it out' but still same
prob.� Before I pull plugs and replace(also cap and rotor) I wanted to ask
advice.� Possible water in tail pipe? Also noticed temp gauge doesn't read
middle like usual. This happened right after rinse.� I had previously
detailed engine last week and all good to beach and back.� TIA
Michael in San Antonio
91GL AT 'Gringo'
73 Beetle