If you have started noticing engine-related issues while driving, you may have to check your fuel pump control module. It is an essential part of an electronic returnless fuel supply system. It controls the amount of voltage delivered to the fuel pump. By controlling the voltage, it ensures the fuel pump gets the right amount of power at any given time and offer optimal fuel delivery to the engine.
Vehicles designed with electronic returnless fuel delivery systems use fuel pump control modules instead of fuel pressure regulators. But where is the fuel pump control module located?
Where is the fuel pump control module located?
The “fuel pump control module” location varies from vehicle to vehicle, but it’s usually at the rear end of the car. You can check your owner’s booklet to know where the fuel pump control module is located.
In most older cars, it is located close to the fuel pump. But this location leads to overheating problems. Now, it is installed at the rear end of your car, under your seat, or on the vehicle floor covered with car carpet.
What does a fuel pump control module do?
To better understand what a fuel pump control module does, let’s see how an electronic returnless fuel supply system works.
The engine control unit (ECU) determines how much fuel pressure is needed at any given time by collecting data from various car sensors, such as the fuel temperature sensor, fuel rail pressure sensor, etc. As the ECU/ECM collects this data, it tells the fuel pump control module the amount of voltage to supply to the fuel pump.
When you start your car, the engine control unit sends voltage to the pump via the fuel pump control module. By doing so, the module controls the fuel pump. If you were asking what controls the fuel pump, now you know.
Symptoms of bad fuel pump control module
The fuel pump control module usually fails due to road vibration, overheating, and corrosion. Hesitation or loss of power, rough idle, engine stalling and misfiring, loud whining noise, engine surges, and bad gas mileage are the most common signs of fuel pump control module failure.
Bad gas mileage
The primary work of the fuel pump control module, also known as the fuel pump driver module, is to tell the fuel pump the right amount of fuel to supply to the engine. So, if the FPDM becomes faulty, the pump may send more fuel than it should. If you notice your car is taking more fuel than usual, have your FPDM checked.
Rough idling
If your car starts running rough on idle, it could mean the fuel pump control module is malfunctioning. The FPDM supplies voltage to the fuel pump and controls how it works. So, if it malfunctions, it will affect the amount of fuel that goes into the engine.
Crank/no start
More often than not, a bad fuel pump will cause a no-start situation, where the vehicle engine cranks but will not start. This happens when the pump control module completely fails and does not send any voltage to the fuel pump. As such, the pump is not sending fuel to the engine for combustion.
Engine stalling/misfiring
If the pump control module malfunctions, it will not send the right voltage to the engine, causing it to stall or misfire. However, you should know that several other factors can cause your engine to misfire/stall.
Engine hesitation/surges
Engine hesitation is one of the most common VW fuel pump control module failure symptoms. Your pump control module is possibly faulty if your engine surges or hesitates while driving. This happens because the control module is not sending the right amount of fuel to the engine.
Loud whining noise
While it’s okay to hear a small humming sound from your fuel tank, you should be concerned when you hear a loud whining noise from underneath the car. The fuel pump could malfunction because of a faulty pump control module.
Poor engine performance
There’s no way your car engine will work at its best if it doesn’t receive the right amount of fuel. If your car is losing power when driving, especially when accelerating, it could be a symptom of a faulty fuel pump control module or any other fuel delivery component.
Please keep in mind that you can experience these symptoms because of different issues in your vehicle. So, have a mechanic diagnose your vehicle before pointing accusing fingers to the FPDM.
What does a faulty fuel pump control module sound like?
The fuel pump control module is prone to corrosion from road debris and chemical compounds on the rads due to its location. Corrosion damages the electronic circuit of the pump control module, making it a “whirring noise.” You will hear the sound more when accelerating or climbing a hill.
How do you reset the fuel pump control module?
If you have an accident, there is a high chance you will reset the pump control module before it starts working again. If the FPDM stops working, you may see a warning on your dashboard asking you to restart your fuel pump module. Here are simplified steps to reset it.
- Turn off the vehicle engine
- Check and fix any fuel leaks in your car
- Once you have ensured there are no more leaks, open the access panel and find the inertia trigger.
- Press the reset button on it to restart the FPDM
- Recheck for fuel leaks
- Switch on your car.
How much does it cost to replace a fuel pump control module?
The cost of replacing a faulty FPDM varies from vehicle to vehicle. However, the replacement should cost between $100 to $700. This does not include labor charges. Labor charges and taxes also vary based on your region, vehicle, and the mechanic doing the job.
Final words
If you have been reading to this point, you will no longer ask, where is a fuel pump control module located? The FPDM is located at the rear end of your car’s underside or on the floor covered with car carpet.
Watch out for the faulty pump control module signs I outline in this article and replace it once you confirm the module is bad. Remember, you must program the pump control module after replacement for optimum operation.
