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Re: ur-quattro idiots/oil pressure

Responding to Bob Gunn's post-

The most important light to verify is oil pressure. It should come on with
the key and go out when the engine starts.

You other UrQ idiots (oh you meant the lights not the owners?) might be
interested in this bit of foolishness:

My oil pressure sender switch died so I went to the local parts place to get
another. As you know, they come in high pressure 20 psi or so and low
pressure 6 psi or so. Well I thought," I know the low pressure one was in
there, but I'll try the high pressure one 'cause maybe I'll see the light in
time to save the engine instead of only in time to call the tow truck."  The
only problem is that  the sense of the switch is backwards. The high pressure
switch closes when the pressure is ok while the low pressure switch opens
when it's ok.  So the light would be on all the time when it should be off.

It turns out that audi ran most of the wiring ( at least in my car) for the
oil pressure lamp control "relay", but instead of using the control switch
and two oil sendors like in the other audi's, they just jumpered across for
the one switch. Go figure?  It would seem that the "relay" could possibly be
installed with minimal effort. Not having the "relay", though,  what I did
was to install a transistor to invert the sense of the high pressure switch.
This requires four wires which can all plug in where the oil control "relay"
should have gone. With this setup, the light  blinks occasionally during hot
idle, but at least I  know it's still working, and I feel a little better
about knowing I have more than a few psi of oil pressure.  What the car
really needs is gages. I can't fathom why these weren't original equipment in
this car!

Concord NH
'83 TQC