This integral two-stage fuel regulator valve uses low pressure, low flow in "cruise" mode but delivers low pressure, high flow once fully opened.

Automotive gauges are simple and have changed little in the last 100 years. Understanding how they function can make troubleshooting a snap. Some background on the basic principles of gauge operation: ...

At this point, the pressure of the fuel is controlled by the fuel pressure regulator and feeds the engine. Any remaining fuel then returns to help refill the surge tank.