Contour Enthusiasts Group Archives Forums General Troubleshooting Fuel Pressure -- AGAIN

Lance,

What you are reporting sounds normal.
Fuel delivery is controlled by the duration of the enabled injector. Since our engines are SEQUENTIALLY injected, we should not require a high fuel pressure.
On a MultiPort injected Engine, Fuel pressures are about 30 - 35 PSI.
Throttlebody injected engine have sustained fuel pressure af abut 17 - 20 PSI.
This sounds low, but the throttlebody injectors are very large.
A small PSI is required with a larger injector.

As vacuum drops (open throttle) your fuel regulater restricts return flow to keep the pressure stabilized. That is the spike you are seeing. When you release the throttle, vacuum spikes, causing the regulator to release the fuel pressure, allowing the additional pressure to flow back to the return line.

Are you viewing this with a fresh Fuel Filter ?

Pete...