Fuel Injector Replacement: What You Need To Know

Fuel injectors are an essential component of a car's fuel system, but the question of when to replace them is a complex one. While some mechanics suggest replacing them at certain mileage intervals, others argue that injectors should last the lifetime of the car and only need to be replaced if they are faulty or defective. This means that there is no definitive answer to the question of when to replace fuel injectors, and car owners should monitor their vehicle's performance and consult reliable sources to make an informed decision.

Fuel injectors should be replaced if they are failing or defective

Fuel injectors are an essential component of your car's engine, so it is important to address any problems as soon as they arise. Fuel injectors should be replaced if they are failing or defective. Here are some signs that indicate your fuel injectors are failing or defective:

Engine Won't Start

If your car won't start, it could be a sign of fuel injector failure. Fuel injectors spray fuel into the engine, and if they are not functioning correctly, the engine won't start. A faulty fuel injector may be unable to deliver the required amount of fuel to the engine, causing issues with starting the vehicle.

Rough Idling

Rough idling is another potential sign of fuel injector issues. This is characterised by a sputtering and shaking of the engine when the vehicle is at a stop or in slow-moving traffic. Normally, the engine should idle smoothly, even when the vehicle is not in motion. Rough idling can also be accompanied by engine stalling, indicating a potential problem with the fuel injectors.

Poor Performance and Lack of Acceleration

Failing fuel injectors can cause a decrease in engine power and acceleration. This may manifest as difficulty in gaining extra speed, such as when trying to overtake another car, or struggling on uphill roads. The fuel injectors supply fuel to the engine, and if they are not working properly, the engine may not be able to generate enough power to maintain optimal performance.

Engine Misfires and Erratic RPMs

Dirty or faulty fuel injectors can disrupt the delicate fuel-air mixture inside the combustion chamber of each cylinder. This imbalance can lead to engine misfires, causing the engine to stutter and the RPM needle to move erratically. You may notice unexpected changes in the RPM gauge, indicating fluctuations in RPM when the vehicle is not shifting gears.

Check Engine Light

The check engine light on your dashboard is a clear indicator that something is amiss with your vehicle. A malfunctioning fuel injector can trigger this warning light, as it disrupts the fuel-air mixture, leading to an error code from the O2 sensor. It is important to pay attention to this warning light and have your vehicle checked by a mechanic to prevent further issues.

If you notice any of these signs, it is advisable to consult a mechanic and consider replacing the fuel injectors to restore the smooth and efficient functioning of your vehicle's engine.

Fuel injectors are not usually replaced as part of scheduled maintenance

In some cases, a dealer may recommend a fuel injector replacement at certain mileage intervals, but this is not standard practice. If your dealer suggests a fuel injector replacement, it is important to ask them why and to get a second opinion if necessary. There may be a known issue with the injectors on your model of car, or they may be trying to get you to pay for an unnecessary repair.

If you are experiencing issues with your fuel injectors, such as leaking or a constant misfire, then it may be necessary to replace them. However, this is not considered scheduled maintenance and is instead a response to a specific problem.

It is always a good idea to keep up with regular maintenance and to address any issues with your vehicle as they arise. However, fuel injector replacement is not typically a part of this routine maintenance and should only be done if there is a clear indication that they are not functioning properly.

Fuel injectors can be replaced at home

When to replace fuel injectors

Fuel injectors should be replaced when they are faulty or defective. There is no recommended interval for replacement. However, there are some signs that indicate a clogged or failing fuel injector. These include a flashing check engine light, engine misfires, rough idling, changes in fuel economy, bad fuel odour or fuel leaks, engine performance issues, and failed emission tests.

The process of replacing fuel injectors

The first step is to let the car cool down and disconnect the battery. Then, locate the fuel injectors on the intake manifold. Use pliers to remove the fuel injector connectors on the fuel rail. Unlock the fuel rail using a socket wrench or screwdriver, and gently remove it. The next step is to wiggle the injectors out of the fuel rail. Purchase new injectors designed for your specific engine and dip the tips in fuel. Reinstall the new injectors, ensuring they are inserted correctly into the manifold. Reattach the connectors and clips that hold the fuel rail in place. Finally, turn the key to the "on" position and wait for 20-30 seconds before starting the engine.

Precautions

It is important to note that replacing fuel injectors can be a challenging and dangerous task. It involves working with gasoline, so there is a risk of causing a gas leak or fire if the procedure is not followed correctly. Therefore, it may be better to have a professional mechanic replace the fuel injectors.

Fuel injector replacement can be expensive

On average, the cost of replacing fuel injectors ranges from $300 to $900 per injector, with some injectors costing several hundred dollars apiece. The cost of parts and labour for the replacement can range from $150 to $400. For example, the cost of replacing all four fuel injectors on a 2019 Toyota Yaris was quoted at $2150+tax.

To save money on fuel injector replacement, you can compare prices and shop around for the best deal. It is also worth considering purchasing refurbished or remanufactured fuel injectors, which can be just as reliable and effective as new injectors but at a lower cost.

Additionally, routine maintenance and the use of high-quality fuel can prolong the life of your injectors and potentially prevent the need for replacement. Fuel injectors typically last between 50,000 and 100,000 miles, or 150,000 miles or more when kept clean.

Fuel injectors may need replacing if there is a drop in MPG or rough running

Fuel injectors are an important component of modern engines, ensuring the right amount of fuel is delivered for combustion. However, they may need to be replaced if there is a drop in fuel efficiency (MPG) or the engine runs roughly.

A drop in MPG can indicate that the fuel injectors are not functioning optimally, leading to reduced fuel efficiency. This can be caused by clogged or failing fuel injectors that deliver too much or too little fuel to the engine. In addition, rough running, including engine misfires and inconsistent idling, can also be a sign that the fuel injectors need attention.

There are several other warning signs that your fuel injectors may need to be replaced. These include a flashing check engine light, difficulty starting the engine, increased stalling, and a failed emission test due to increased emissions. If you notice any of these issues, it is important to have your vehicle inspected by a qualified mechanic as soon as possible to prevent further engine damage and costly repairs.

It is worth noting that fuel injectors are generally designed to last the lifetime of a vehicle. However, certain factors such as age, condition, and the type of fuel system can contribute to their deterioration. Regular maintenance and cleaning can help prolong the life of fuel injectors and prevent performance issues. Cleaning is a cheaper alternative to replacement, but it may not solve severe issues and can be unnecessary if replacement is required.

If you decide to replace your fuel injectors, the cost can vary depending on your vehicle's make and model, your location, and whether you replace one or all of the injectors. It is generally recommended to consult a trained mechanic for this process.

Frequently asked questions