The fuel pump drive -- or driver -- module is usually referred to by the acronym FPDM. Aftermarket retailers sometimes call the same component a fuel solenoid driver, or FSD. By either name, the module controls the voltage delivered to a vehicle’s fuel pump. By controlling the voltage, the fuel-pump driver module maintains the optimum fuel pressure and fuel delivery to the engine throughout its full operating range.
Where is my fuel pump driver module located on my 2001 Ford F150 5.4L engine. It's not behind the spare - Answered by a verified Ford Mechanic.
Purpose
The fuel-pump driver module controls the high-pressure fuel pumps of modern, computer-controlled, fuel-injected engines, including diesels. The module is typically installed on or very close to the fuel pump, and in the early years of the component's use, this practice led to a design fault. Manufacturers, including Ford, initially placed the module inside the vehicle immediately above the fuel pump, typically just beneath the floor pan. That practice had the module mounted under seats or covered by carpet, which led to overheating problems.
Failure
The fuel-pump driver module is the most common part to fail in computerized diesel engines. When first installed in the technologically advanced diesel engines of the mid-1990s, the modules were made from materials that were unable to handle their own high operating temperatures and the extreme vibration they were exposed to when functioning. In some model vehicles, such as General Motors vehicles made between 1995 and 2002, the failure rate has been almost total. Aftermarket units are available that use advanced electronics that create less heat, with an improved heat transfer pad to minimize retention of the heat. Pairing the fuel-pump driver module with the incorrect fuel pump will also promote failure.
Symptoms of Failure
Symptoms of a failing fuel-pump driver module all manifest in the performance of the engine. Difficulty in starting or a smoky start-up, stalling or uneven running while idling, hesitations and misses when driving, and power surges when in reverse can all -- separately or together -- be indicative of a failing module. Failure can normally be diagnosed electronically using a handheld scanner, with the model-specific code displayed that translates to the fuel-pump driver module.
Modified Engines
Vehicles with modified engines that need more fuel than is standard, such as race cars and tuned-up street cars, require modified FPDMs. Running a standard module can result in overheating -- the standard fuel pump asks too much of the module, and its electronics overheat -- so the internal limiter shuts the control process down. Although the module should resume function when it cools to a safe temperature, the sudden cessation of fuel flow to a full-revving engine can have catastrophic effects.
- Jupiterimages/Photos.com/Getty Images
More Articles
$92.73 - $160.32
The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an internal combustion engine. It is often found in the fuse box located in the engine bay and functions as the primary electronic switch that controls power to the fuel pump. The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function. As the fuel pump relay controls power to the fuel pump, any faults with it can cause issues with the fuel pump, which can cause drivability problems for the vehicle. Usually a bad or failing fuel pump relay will produce a few symptoms that can alert the driver of the issues.
1. Engine stalls
One of the first symptoms of an issue with the fuel pump relay is an engine that suddenly stalls. If the fuel pump relay has an issue while the vehicle is operating it will cut off power to the fuel pump, which will cause the engine to stall. A faulty relay may allow the vehicle to be restarted a short while later, while a completely failed relay will not.
2. Engine does not start
Another symptom of a faulty fuel pump relay is an engine that does not start. If the fuel pump relay fails the fuel pump will be left without power. The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel. This symptom can also be caused by a wide variety of other issues, so having the vehicle properly diagnosed is highly recommended.
2. No noise from the fuel pump
Another symptom that may hint at an issue with the fuel pump relay is no noise from the fuel pump when the key is switched on. Most fuel pumps will produce a low volume hum or whine which can be heard from the inside the vehicle if listened for closely, or from the outside of the vehicle, near the fuel tank. If the fuel pump relay fails, it will cut off power to the fuel pump which will render it inoperable, and therefore silent, when the ignition is on.
While the fuel pump relay is a very simple component, it plays a very important role in the proper operation of the vehicle. If your vehicle is displaying any of the symptoms above, or you suspect that your fuel pump relay is having an an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the component should be replaced.
Next Step
Schedule Oil Change
Engine oil is the lifeblood of the engine. The oil resides in the oil pan, which is under the car attached to the bottom of the engine. All internal (moving) parts of the engine need to be lubricated by the engine oil. Inadequate lubrication will cause the parts to wear out faster and eventually lea... LEARN MORE