Here's a couple of images of my cluster. Notice the vacuum gauge.
Heres the vacuum gauge in Park - with the engine warmed.
Here's an image with the transmission in idle.
Note that the car has just passed the 200000 Kilometres mark.
If your vacuum is not at those levels you will not get optimum M.P.G. and low end performance.
This car idles very silently - the heater fan is noisier the the engine at idle. Very good M.P.G.
The last item I replaced was the valve for the return fuel to the charcoal canister. It seemed like there was a leak from that. I also replaced the inlet manifold gasket.