low oil pressure 1989 type 44 turbo - solved?

[Graham Thackrah]

Hi all,

Many thanks for the replies to my low oil pressure query. The reason I
posted is that I know what my guage *usually* does, it usually hits 5
bar at cold idle, then drops as it warms and thins, but it always used
to hit 5 bar when revved, even when thoroughly warmed up. The other
night was the warmest that I'd driven the car and I noticed the lower
guage reading when cracking along at 90 and also noticed the oil warmer
than its ever been (midway between the mark above 60 and the 130 mark -
was probably pulling a fairly constant 0.7 to 0.9 bar +/- at the time).
But even on the trip back later in the evening, with oil temps above 60
but below the next mark (I was taking it easy), the pressure never got
above the 3 bar line when it always used to read c. 4-5 bar.

To answer a few questions, I've always filled it with VAG synta gold, a
fully synthetic 5w 40 multigrade, changed every 3-4k miles, the filter
was bought from an Audi dealer and has "Audi Turbo" and part number 035
115 561 written on the side of it, if it's not OE, I want my money
back;) The motor has c. 82k miles on it - indicated, not verified.

I just checked the sender, ign. off, it reads c. 30 ohms, warm idle it
reads 150-160 ohms and when revved to 3k it reads 210 ohms, comparing
that to the specs on Phil Payne's website
http://www.isham-research.com/quattro/oil_test.html - they seem high to
me. should be 5-10, 70-120 and 170-200 respectively, at least for the MB
ur-q. Seems to me that could well be the cause but would higher
resistance cause the guage to read low?

Cheers,

Graham.