First time on message board and new '87 GN owner. The car' VDO Oil Pressure gauge in electronic, and the gauge's scale is from 0-150 lbs per sq inch. When the car is first started (cold) the gauge shows approx. 125 lbs. Once it warms up and is idleing it runs at approx. 35 lbs and under acceleration warm it runs at approx. 85-90 lbs. Any ideas?