Role of a Fuel Pressure Regulator in Car

A fuel pressure regulator is a device used to maintain constant fuel supply, even during dramatic changes in the fuel demand.

It is included in every fuel- injected vehicle for delivering an exact amount of pressure at the nozzle of the injector during operation.

Fuel pressure regulators help in maintaining the set pressure for the smooth running of the vehicle.

Working of a fuel pressure regulator

The fuel pressure regulator mainly consists of a diaphragm that controls the bypass valve “ball seat” to open and close in order to adjust itself for a steady fuel delivery.

When pressure is applied to the top of the regulator, a spring forces the diaphragm down and reduces the amount of excess fuel.

This puts more load on the fuel pump while the fuel pressure increases linearly towards the required boost pressure from the intake manifold.

Purpose of a fuel pressure regulator

It is an essential component of any Electronic Fuel Ingestion(EFI) system to build up enough pressure to support the injectors with the sufficient amount of fuel.

To accommodate a successful fuel and air mixture, a proper fuel pressure is required in all situations, both at low revs and high revs, regardless of the power output.

This is where the fuel pressure regulator is doing its job, to adjust the fuel supply to the fuel demand.

Importance of maintaining the right fuel pressure

The real importance of the fuel pressure regulator is felt when it starts malfunctioning and fails to maintain the appropriate fuel pressure.

When the fuel pressure regulator is not working properly, then these signs are immediately seen in your car:  Burned spark plugs  Emission of black smoke  Smell of fuel from the dipstick  Fuel in the vacuum hose

While checking the spark plugs, if you find that one end of the plug is blackened, then be sure that the engine is burning fuel at that end. It is better to replace the burnt spark plugs along with the malfunctioning fuel pressure regulator. Burned spark plugs

Generally, the color of the smoke from the exhaust is white or gray, but not black. The moment you find black smoke coming out of the car's tailpipe, then be sure that the fuel pressure regulator is malfunctioning. Emission of black smoke

While checking the oil level, if you smell fuel on it, then it might be the result of a bad fuel pressure regulator. The failing fuel pressure regulator would have allowed gasoline to leak into the oil system. Smell of fuel from the dipstick

Making sure that the engine isn't running, remove the vacuum hose that is attached to the fuel pressure regulator and check for the presence of fuel. If fuel is present, then it is a clear indication that the fuel pressure regulator is failing and allowing the fuel to pass through the hose. Fuel in the vacuum hose