1986 Audi 90 oil pressure warning light

[David Boyd <john@dboyd.demon.co.uk>]

I have been too attached to my old Audi 90 to take too much trouble to
sell it since I replaced it, so it has stood for over six months and I
have not run the engine as often as I should.

On doing so today, contemplating whether to get rid of it or try to get
my son insured to drive it, the oil pressure warning light is coming on
at 2000 to 6000 rpm; up to 2000 it's OK and it was fine when I stopped
using the car.

It seems to be the bottom of the two pressure switches on the block
which is operating the warning light in this case - disconnecting the
single spade connector extinguishes it. 

Is this purely a low pressure switch or does it illuminate if pressure
is too high - I am wondering if the relief valve has stuck or if the oil
has turned to treacle somewhere.

I suppose next step would be to eliminate the possibility of a bad
sender by swapping it - I may have one lying about somewhere, but any
suggestions/observations meanwhile would be appreciated. The engine is a
5cyl. JS.


-- 
David Boyd
Cumbria, UK
mailto:david@dboyd.demon.co.uk