An HPOP Pressure Gauge is used to measure the volume of oil which controls the injector's pressure. If you have a weak pump, one of these gauges will let you know that your engine won't be getting enough fuel from each injector in order to run the right way. Performance chips and programmers often demand a greater volume of fuel than what is running, causing a dramatic decrease in HPOP Pressure. This prevents you from obtaining the performance increase that your chip is capable of providing.
More on HPOP Pressure Gauges - Diesel Trucks & More
HPOP Pressure Gauges typically display a range of about 3000 PSI on stock trucks, which is the normal amount of pressure for the stock system. Aftermarket trucks definitely need an HPOP Pressure Gauge in order to ensure that enough fuel is being squirted fast enough into your injectors.