!985 380SL, 240k mi., the motor feels strong

While cruising at 40 or so MPH the oil pressure reads 3 bars if I let off the accelerator it may drop to 2.75 or so BUT as I come to a stop the pressure drops to 0 while the idle is abound 5 - 700 RPMs. I usually shift to neutral, the revs increase and the needle bounces between 1 and 2. Should I have the car towed to the shop?

Thank you for any replys