These voltage standards for the fuel pump relay are for the consistency and dependability of the fuel pump, which usually operates within a constant 12 volts of power. Most automotive systems use 12 volts. Also, in such fuel pump relays, their design in handling such a volt rating is used to turn on the pump with the ignition. A deviation from this standard-for instance, drops below 11 volts or surges above 14 volts-may create unstable fuel delivery and thus may cause problems with the vehicle, such as engine stalling or failure to start.
Voltage drops in the relay reduce fuel pump efficiency since the insufficient voltage will prevent the relay from completing the circuit. If the voltage is not enough at the relay, pulling the contacts in all the way will not occur; if the contacts don't pull in all the way, that could result in intermittent power to the fuel pump, which in turn could lead to fluctuating pressure. Most fuel systems operate within a set range of pressure-usually between 30-80 psi, depending on the engine design. Voltage problems are often encountered by technicians in models of older years as the worn wiring out increases resistance, dropping relay voltage and fuel pump performance.
High-performance applications may require higher voltage tolerances in relays, especially when the vehicle has modified electrical systems that require a little more current. Sometimes such performance relays are rated for up to 14 volts, making sure slight increases due to increased load will not affect fuel delivery. In this regard, mechanics normally recommend upgrading to a relay that can handle such tolerances when modifying vehicles for performance, reducing the risk of fuel pump issues under high loads.
The voltage regulators installed in high-demand vehicles serve to hold a constant 12-volt supply. The voltage regulators keep the voltage spikes or drops away from the relay and fuel pump, hence enhancing the life of the system. In hot countries or vehicles that go through frequent high electrical demands, regulators ensure the relay functions perfectly, with elimination of wear by voltage stress.
As once coined by automotive pioneer Lee Iacocca, "Quality is job one." What a Fuel Pump relay needs for proper working and functionality of fuel system reliability are voltage standards it has to comply with. Check out Fuel Pump at for reliable fuel pump relay options and more.