The fuel pressure regulator controls the fuel pressure in your Ford’s fuel system, maintaining the proper pressure needed for your vehicle to run optimally. If the fuel pressure regulator malfunctions or fails completely, one or more symptoms will occur. While testing will need to be performed to verify the failure, if any of these symptoms are present, a faulty fuel pressure regulator may be to blame.
Slow or No Start
Part of the fuel pressure regulator’s job is to maintain fuel pressure at the fuel injectors at all times, including when the engine is shut off. A fuel injected vehicle, with proper fuel pressure, will start up quickly, if no other malfunctions are occurring. In the event your Ford cranks easily, but doesn’t start within the first five or six revolutions of the starter motor, you may have a faulty fuel pressure regulator. If the regulator has failed completely, the vehicle will crank, but not start at all. Avoid cranking the starter for too long, or you will burn it up and add the starter to your list of needed parts.
Under acceleration, the vehicle should accelerate smoothly no matter how hard or light the accelerator is depressed. If the Ford will not accelerate smoothly, but instead jerks and jumps under acceleration, your fuel pressure regulator should be inspected.
A poor fuel pressure regulator can also cause your Ford to stall while idling or driving. While it will most likely occur while idling, it is not unheard of for the car to stall while you are driving down the road. If the fuel pressure regulator is not maintaining exact fuel pressure while the engine is running, it can cause the engine to run rich or lean, and in the event it goes too far in either direction, the engine will stall out due to an inability to properly burn the air/fuel mixture. Gasoline needs air to burn. In an overly rich scenario, there is not enough air for the mixture to achieve combustion; if there is too little air, the combustion will also fail to occur. Since the fuel pressure regulator is given specific air/fuel mixture directions from the PCM, it should always maintain the proper mixture.
A faulty fuel pressure regulator can also be to blame for a sudden decrease in fuel mileage.
These symptoms can also occur with a plugged fuel filter, failing fuel pump, or faulty PCM. In the event you have these symptoms, it is best to have the entire fuel system inspected by a qualified Ford fuel system technician.