Replacing Fuel Injectors In Your Ford F-350: Step-By-Step Guide

If you're experiencing issues with your 2006 Ford F-350 Super Duty, you may need to replace the fuel injector. Fuel injectors regulate the amount of pressurized fuel used for each engine cycle and a faulty one can cause engine misfires and a reduction in engine power. While it is recommended that you get the fuel injector replaced by a professional, here's a step-by-step guide on how to do it yourself.

When to replace the fuel injector

Fuel injectors are metering devices that spray atomized droplets of fuel into the engine's intake manifold or combustion chamber. They are usually connected to a fuel rail located on top of the engine and supplied with fuel from the fuel pump in the fuel tank.

• Rough idle, loss of power, or misfiring: Poor engine operation can have many causes, but faults in the fuel injection system, including the fuel injectors, are often high on the list of possibilities.
• Odor of raw gas or visible leaks: Fuel injectors should not leak fuel into the intake manifold when the car is off. If you notice any fuel odour around your car, a leaking fuel injector could be the culprit.
• Check engine light: Some fuel injection failures, such as a faulty solenoid, may cause a trouble code to be set in the PCM (powertrain control module), illuminating the check engine light.
• Major engine repairs, engine replacement, or lengthy storage: All fuel injectors will develop deposits over time and with mileage. These deposits can cause an imbalance in the performance of the injectors from cylinder to cylinder. Therefore, when the engine is disassembled or if you are installing a new engine, it is an ideal time to service or replace the injectors as a set.
• Reduced engine power and frequent misfires: When a fuel injector fails or clogs, it can lead to a reduction in engine power and frequent misfires.
• Engine stalling, hesitation, or rough vibration: As the issue with a faulty fuel injector progresses, the engine may exhibit more severe symptoms such as stalling immediately after starting, hesitating under throttle, or vibrating roughly.

How mechanics replace a fuel injector

Mechanics follow a careful procedure to replace a fuel injector on a 2006 Ford F-350 Super Duty. Here is a detailed, step-by-step guide on how mechanics typically perform this repair:

Firstly, safety is paramount when working with fuel systems, so the battery should be disconnected, and proper precautions should be taken to prevent any fire hazards. Next, the engine should be allowed to cool down, and then the pressure in the fuel rail is relieved by briefly running the engine with the fuel pump fuse removed.

The next step is to gain access to the fuel injectors. This involves removing the upper plenum on the intake manifold, along with any cables, hoses, or wiring that may be obstructing the area. Once the area is clear, the supply and return lines are disconnected from the fuel rail, and the electrical connectors to each fuel injector are unlocked and carefully removed.

At this point, the fuel rail is unbolted and lifted out of the intake manifold. The mechanic will then identify the faulty injector(s) and remove them from the fuel rail, being careful not to let any debris enter the exposed openings. The injector is usually held in place by an O-ring seal, which needs to be replaced with a new one when the serviced or new injector is installed. It is important to use engine oil on the new O-ring to prevent any damage during the installation process.

Once the new or serviced injector is securely in place, the fuel rail is reinstalled, and the supply and return lines are reconnected. The plenum and any other components that were removed to gain access are then reinstalled.

Finally, the engine is started, and a careful check for leaks is performed. A road test is then conducted to ensure the vehicle is operating correctly.

It is important to note that fuel injector replacement is a complex task and should be left to professional mechanics.

The cost of replacement

The cost of replacing a fuel injector on a 2006 Ford F-350 Super Duty V10-6.8L depends on whether you take your car to a shop or dealer, or call out a mobile mechanic.

The shop or dealer price is estimated to be between $2,502.60 and $3,847.00. This includes parts, priced between $973 and $1,084, and labor, estimated to be between $229 and $289.

However, if you opt for a mobile mechanic, the price is likely to be lower, at around $635, with $439 for parts and $196 for labor.

It is important to note that prices may vary depending on your location, and related repairs may also be needed, which will increase the overall cost.

Symptoms of a bad fuel injector

• Engine misfires and reduced power: A bad fuel injector can cause the engine to misfire, making the motor feel like it is sputtering and sending vibrations through the car. This can happen when a fuel injector problem disrupts the delicate balance between fuel and air entering the engine. With at least one cylinder starved of fuel, the engine will rapidly lose power, and you may find it hard to accelerate or maintain speed.
• Rough idling: A faulty fuel injector can cause the engine to idle roughly, sputtering and shaking as it struggles to stay running.
• Poor fuel economy: Well-performing fuel injectors help your vehicle achieve optimal fuel economy. If you find yourself filling up at the pump more often than usual, it could be a sign that your fuel injectors are not functioning properly.
• Unusual behaviour of the RPM needle: Dirty fuel injectors can cause the needle on the tachometer (the gauge that displays the vehicle's RPM) to move erratically or unprompted, indicating changes in RPM when your car isn't switching gears.
• Engine won't start: In rare cases, fuel injector issues can lead to engine failure and prevent your car from starting. This occurs when the engine doesn't receive the necessary combination of air and fuel, disrupting the required combustion process.
• Check engine light is on: The check engine light on your dashboard could be illuminated for various reasons, one of which could be a faulty fuel injector. This warning light indicates that the fuel injector may be dirty or malfunctioning, supplying too little or too much fuel to the engine, resulting in decreased engine performance and fuel economy.
• Fuel leaks: Over time, the heat and moisture can take a toll on the fuel injector, leading to cracks in the rubber seals or the injector itself. A fuel leak is a clear sign that the fuel injector needs attention.

Fuel injector control module

The fuel injector control module (FICM) is a high-voltage driver for the fuel injectors, which are controlled by the vehicle's electronic control module (ECM). The ECM can be thought of as a low-voltage processor that assesses the engine and cab sensors and calculates and commands a volume of fuel from each injector.

The FICM sends a ~0.6-millisecond duration ~48v (DC voltage) to the 'on coil', which creates a magnetic field and draws the spool (metal rod) to the open position, allowing high-pressure oil to push down on the injector's internal plunger. The FICM then sends a second 0.6-millisecond duration ~48v to the 'off coil', which pulls the rod/spool back to its closed position. The time between these two signals is the injector on time, or Injector Pulse Width (IPW).

A common failure with the FICM is 'low voltage', which is caused by internal circuit board components aging, wearing, and deteriorating, preventing the FICM from outputting the proper voltage to the injector coils. This can cause very hard or no starts, especially in colder temperatures.

There are several options for replacement FICMs for the 2006 Ford F-350 Super Duty, including:

• Dorman OE Solutions Injection Control Module - New - 904-229: A new FICM with a limited lifetime warranty, 12-volt voltage, and a 4-pin design.
• Standard Ignition Fuel Injector Control Module - FICM4: A remanufactured FICM with a limited lifetime warranty, 48-volt voltage, and a 54-terminal design.
• Cardone Fuel Injector Control Module - Remanufactured - 78-2004F: A remanufactured FICM with a 1-year limited warranty, 48-volt voltage, and a 54-terminal design. Requires vehicle-specific flash programming.

Frequently asked questions