Symptoms of Failure of Fuel Pressure Regulator and How to Replace it

By | September 3, 2014

Fuel pressure regulators are primarily used in fuel injector cars. The fuel pressure regulator regulates the pressure of the fuel before it goes to the fuel injector. In fuel injection system is a high pressure system. This high pressure system is produced in fuel pump and regulated by the fuel pressure regulator. The fuel pressure regulator ensures that the system maintains the proper amount of pressurization.

Where is the fuel pressure regulator located?

  • The fuel pressure regulator is located in different places depending upon the vehicle type/ model.
  • For some vehicles/cars, it’s mounted in the fuel rail due to this the extra fuel flowing from the fuel rail through the fuel pressure regulator will enter the fuel return line and it can travel back to the fuel tank.
  • For some vehicles, the vehicles the fuel pressure regulator is located inside the fuel tank mounted.
  • In some cases, even the fuel filter is part of the assembly, making it expensive to replace.
  • Regardless of its location, the job of fuel pressure regulator is same and that is to maintain constant fuel pressure to meet the engine needs.

Symptoms of failure of fuel pressure regulator
Symptoms of failure of the fuel pressure regulator are as follows:

  • Spark plugs blackened.
  • Engine doesn’t run smoothly.
  • Emits black smoke.

Spark plugs blackened

  • Remove one of spark plugs from your car and examine the end of it.
  • If the spark plug is black, it is one of the signs of a bad fuel pressure regulator.
  • If you find one of the sparks plug in this condition, check the rest of them.
  • If only one spark plug is black, it means the engine is burning oil at that location.
  • The regulator could be clogged. You can simply clean them and put them back, but if your engine still runs poorly, replace with a new pressure regulator.

Engine running harshly

  • When you are idling the engine and it is not running smoothly, if it is spitting badly, change your oil filter unless it’s new one.
  • Even then if it doesn’t work, check your pressure regulator.
  • Another sign that your engine is affected by a bad fuel pressure regulator is if you have trouble starting the car.

Exhaust black smoke

  • When black smoke coming out of your exhaust pipe is one of the symptoms that there is something bad with your fuel pressure regulator.
  • Replace the fuel pressure regulator.

How to replace a fuel injector

  • First, switch off the engine of your car and locate the fuel pressure regulator.
  • Then, remove the hoses, wires and other parts that are near by the fuel pressure regulator.
  • Locate the bolts, screws that hold the fuel pressure regulator and remove them.
  • On some vehicles, the regulator is part of the fuel pump module.
  • In such cases, remove the module’s upper and lower sections, disconnect and replace the section with the regulator.
  • Place the new regulator the engine and tighten any bolts.
  • Reconnect all lines and connectors attached to the regulator.
  • Use a small screwdriver to remove any residues.
  • Re-pressurize the fuel pressure regulator and reconnect all the oil pump relay and and battery cables.
  • Turn the ignition switch to “On” position for a couple of seconds.
  • Turn off. Repeat the ignition switch another two or three times.
  • Check if the pressure regulator is working properly without any issue.