How Long Does It Take To Replace A Fuel Injector? [Cost]

Replacing a fuel injector is not on the list of most difficult car repair jobs, but that doesn’t make it simple. Repairing a clutch, transmission, or replacing a spark plug is more complicated and takes a lot of time. But, is it difficult, and how long does it take to replace a fuel injector?

Replacing a fuel injector is a difficult and time-consuming task. It takes 1-2 hours for an experienced mechanic to replace the fuel injector. If you want to do it yourself, and you don’t have mechanical experience, prepare to spend at least 2 hours per fuel injector.

Once you decide to replace one bad injector, it is a good idea to replace them all. Depending on the number of injectors in the engine that can take up to 12 hours. Is it better to change the injectors yourself or you should hire a mechanic? What are the signals that the fuel injector is bad? Stay with us, and we will answer these and other injector-related questions.

Average Labor Time for Fuel Injector Replacement 

Labor time needed for injector replacement depends on the model of the car and the mechanic. But, today some specialized mechanics deal with fuel injectors daily. Those mechanics can replace a faulty fuel injector in just an hour. 

Regular mechanics don’t deal with fuel injectors every day. They will need a bit more time, between 1 and 2 hours.

How Long Does It Take to Replace 6 Fuel Injectors?

Replacing 6 fuel injectors altogether is a serious job. After a couple of hours, energy levels and concentration go down. A mechanic doing this job properly may take up to 12 hours.

How Long Does It Take to Replace 4 Fuel Injectors?

Replacing 4 fuel injectors can take between 4 and 8 hours. A mechanic will usually replace 4 fuel injectors in 6 hours.

Factors Influencing Fuel Injector Replacement Time

Replacing injectors is a difficult and complex job requiring special tools and experience. If you decide to replace the injectors yourself, you will need more time than a trained professional.

DIY vs. Professional Fuel Injector Replacement

A mechanic that is dealing with fuel injectors often knows this process, and won’t lose much time tinkering about every step. Depending on the car and the number of injectors, it may take him between 4 and 12 hours to replace the whole set.

Number of Fuel Injectors To Be Replaced

As the number of injectors grows, the time for their replacement lengthens. Even a professional can lose concentration and strength which will slow down the work. Sometimes if he is not able, the mechanic will leave a part of the job for the next day. 

Fuel Injector Replacement Cost: What’s the Price?

The labor price is one factor that intensifies drivers to try and replace the injectors themselves. But, before you try this be sure that you read and viewed enough material to begin this difficult task. 

The price of replacing injectors falls on two factors, the price of the injector, and the cost of the mechanic labor. The price of the injector depends on the model of the car and can fall anywhere between $150 and $400. The labor price varies between $100 and several hundred dollars. 

Is It Worth Replacing Fuel Injectors?

Since fuel injectors are one of the key components of the engine, they need to be replaced. Driving with bad or old injectors will cause problems in everyday driving and make it unsafe and difficult. Before you decide to replace the injectors, the mechanic should inspect them. In some cases, the injectors are just dirty. Then there is an option to clean the injectors, which you should leave to the mechanic.

You should replace the fuel injectors, only after the mechanic’s inspection and diagnostics of an injector failure issue. Then you should replace the whole set of injectors, to avoid repeating the same situation from time to time.

Signs When To Replace Fuel Injectors

Faulty fuel injectors will impact your everyday drive and engine performance, and you will notice several symptoms. 

• The engine misfires. You will have a feeling that the engine is sputtering and sending vibrations through the entire car. When the injectors are dirty, they will mess up the air-to-fuel ratio entering the engine. That ratio is essential for the combustion process. If the ratio is off, then the combustion will go bad. That will result in a rich or lean state, causing engine misfires.
• Problems with rough idling. Rough idling is when you notice that the engine and the rest of the car are shaking and vibrating while you are at a traffic stop or caught in a gridlock. There are a lot of causes for rough idling, and worn and dirty fuel injectors are one of the first parts to check.
• Fuel consumption rises. If you have a problem with a defective fuel injector, then the engine cannot run as smoothly as it should. The combustion will go bad, increasing fuel consumption.
• The RPMs unexpectedly jump up and down. The RPMs move when you add gas and when the gears change. If you notice sudden jumps on RPMs when the gears are not changing, dirty and old injectors can cause it.
• There is a fuel leak. Although fuel injectors are sturdy, they are exposed to constant heat and moisture. That condition comes with consequences. If there is a fuel leak, the reason for it can be the crack in the seals or the injector itself.
• A check engine light is on. Yes, this is a symptom of so many problems. But, if you have an OBD-II scanner, you can check if there are errors that are connected to bad fuel injectors. If you detect any codes between P0171 and P0175 code, then you have a problem with a too-lean or too-rich fuel mix. That is often a result of a faulty fuel injector
• Dark smoke coming out of the tailpipe. In regular situations, you won’t notice smoke coming out of the tailpipe. But, if you notice a black cloud of smoke every time you press the gas pedal, you should check the injectors. When there is too much fuel in the combustion, that can lead to burning extra fuel, resulting in black smoke
• Having trouble starting the car. If you have to rev the engine a couple of times, then maybe not enough fuel is reaching the engine. The culprit behind it is often a faulty or dirty injector. There are cases when the injectors are so damaged that the engine cannot start no matter what you do to it.

Most of these symptoms can imply that there is a problem with several parts of the engine. But, with the help of the diagnostic tool, you can easily detect what parts are causing the problems. Besides the P0171 to P0175 codes, also look out for the P0253, P0261, and P0266 codes.

Check Out 🚩 🚩Red Flags: Symptoms of Faulty Fuel Injector:

Can I Replace the Fuel Injectors Myself?

If you are ready to learn, have some basic mechanical knowledge, and have excess time, then you can. But, you need to be extra careful when doing so. Fuel injectors are an essential part of the fuel system. They have to be properly installed to work as intended.

Steps for Fuel Injector Replacement

Before starting, you should know that you are dealing with fuel which can be dangerous. We recommend using safety equipment like goggles and gloves.

1. Place the car on a flat surface and activate the parking brake. Let the engine completely cool down. When the engine is cold, disconnect the car’s battery.
2. Find the intake manifold. The intake manifold is made from 4 to 8 pipes that are going to the engine. They are located behind the engine. The fuel injectors are the connectors running from the fuel rail to the intake manifold.
3. Disconnect the main fuel line from the rail. So sometimes there is an additional line at the other end of the rail. Disconnect it also.
4. Remove the fuel injector electrical connectors from the fuel rail. For this, you will need pliers. The connectors have cables that are moving away from the fuel rail and the engine. On most connectors, there are tabs on their side that you need to press with a plier to release them. That way you will free up the fuel rail, and you can safely remove it without damaging anything. In some cars, you need to relieve the pressure in the fuel line before you remove the rail. For further information, check the instruction manual.
5. Unlock the fuel rail. This step can vary, and you need to check how the fuel rail is connected to the intake manifold. It can be secured with bolts, screws, or clips. Use the screwdriver to loosen all the connections. If there is any wiring going over the fuel rail, disconnect it first. Once the path is clear, you can safely remove the fuel rail in one piece. Place the fuel rail on top of an old rag so it can soak any leftover fuel. If the car doesn’t have a fuel rail, you will need to remove the fuel line from the top of each injector.
6. Disconnect the fuel injectors. Each injector has a plug at the top that is connected to the wiring harness. Usually, the injector wiring plugs are secured in place with the help of a wire. To remove the wire use a flathead screwdriver. Insert the screwdriver between the plug and the wire and pry it open carefully. It is easy to remove it. Do not lose it because you will need it.
7. Pull out the injectors. Before this final step, take a few pictures of the setup so you can have a reference when installing new injectors. Be extra careful when removing the injectors. They are placed in an important part of the engine. If any part of the injector breaks off, it can end up in the wrong place. To avoid this we recommend using a special tool called an injector puller. Place the puller under the lip of the injector housing and pop the injector out of its place. Once you remove the injectors, you leave several holes in the intake manifold. Be careful, and do not let anything fall in.
8. Lubricate the new injectors. Buy the injectors that are recommended for your car model. Dip the end of the new injectors into a bowl with fuel. That way you will lubricate the new O rings, and avoid any fuel leaks when you install the injectors. Never use the O rings from the old injectors. They are prone to wear and can crack causing a fuel leak.
9. Install the new injectors into the slots on the fuel rail. Check the photographs of the old setup, and install the new injectors in the same way. The end of the injector that has clips goes into the fuel rail. The side that you dipped into the fuel needs to face the intake manifold
10. Line the injectors with the correct holes in the engine. To do so, raise the fuel rail and line up the injectors with the holes. Slowly connect the injectors to the engine. Add security wire if the injector has it
11. Secure the fuel rail and reconnect the electronic connectors. Reattach any screws, bolts, or clips holding everything in place. If the fuel rail had a cover, replace it with a new one. Reconnect the fuel line so the rail can get fuel pressure.
12. Reconnect the battery and start the car. Insert the key into the ignition and turn it to the on position, but do not start the car just yet. Wait about 30 seconds before starting the engine. The fuel rail will fill with fuel, and now you can turn the engine on.
13. Let the engine work and check for any leaks. It will take a couple of minutes for the system to equalize and refill. Turn off the engine and check for any leaks from the injectors or the fuel rail.

Check Out How to Replace Fuel Injectors in Your Car?:

Risks of Delaying Fuel Injector Replacement

Symptoms of bad fuel injectors will make a driver address this issue as soon as possible. The performance and drivability of the car will suffer. Driving a car with a bad fuel injector is torture, and can be unsafe. But, in case you do not replace fuel injectors on time you are risking some serious damage. 

• Hydro locking. If the injector fails in a way to dump fuel constantly into the cylinder, that can trigger an engine hydro lock. There is a spot in the combustion chamber where vapor and gasses are compressed. If it is filled with fluid that can result in a bent connecting rod, damaged piston, or something worse
• Bearing damage. If the fuel injector is leaking it will mix with oil. That will cause both oil and fuel contamination. If the bearings are not properly lubricated with oil they can get seriously damaged
• Damaged catalytic converter. If a damaged injector is leaking fuel it can enter the catalytic converter. If unburned fuel enters the CAT converter it can combust inside it. That will produce high temperatures in the converter permanently damaging it. Since converters are very expensive, you don’t want to drive with leaking injectors
• Flooded engine cylinders. Just like with hydro locking, damaged injectors can leak fuel into the cylinders. The leaks can be so massive that they can fill up the cylinder. When that happens, you will not be able to start the engine. 

FAQs

Is It A Big Job To Replace Fuel Injector?

If you are replacing a fuel injector yourself, it can be a big job. You need some special tools and experience so you can tackle this operation alone. Some tips are hard to find online, and you can learn them only from a professional.

For a professional replacing a fuel injector can be a difficult task. That depends on the type of car, the number of injectors, and the overall state of the system. 

Should I Replace All 4 Injectors?

Yes, you should replace all 4 injectors at the same time. That will save time, money, and effort to do it. Once the mechanic starts replacing one bad fuel injector, then it is easier to finish the whole job. That way you will also have a whole set of new injectors. Their work life will begin at the same time, and you will not need to worry about injectors for a long time.

If you decide to replace only the injector that is in the worst condition, then you will have to deal with the rest of them sooner or later.

What Mileage Should Fuel Injectors Be Replaced?

Injectors should be replaced every 50,000 to 100,000 miles. On Duramax engines that time is prolonged to 150,000 miles. This is a big difference in mileage, and it depends on several factors. The most important input is the quality of the injectors. OEM injectors are always recommended, and they can last longer than most aftermarket parts.

Also, maintenance of the car will shorten or prolong the injector’s work life. If the car is properly driven and maintained, the injectors will appreciate that. They will work better and longer. If the car is neglected, the injectors won’t last that long.

How Long It Would Take To Clean Fuel Injectors?

Depending on your skill level, it can take from an hour to several hours. To clean the injectors you need to connect the fuel rail to a pressurized fuel cleaner. It is set to a certain PSI value, and it is run through the system until the injectors are cleaned.

There is a second option, but it doesn’t show very good results. You can try cleaning the injectors with fuel additives. This is recommended more as a prevention measure than an actual fix.

Can You Clean Fuel Injectors Instead of Replacing Them?

If the fuel injectors are dirty, then you can try to clean them. That way, you will not get the same results as if using new injectors. But, that way you will delay the need for injector replacement for some time. If there are other signs of damage, then cleaning won’t do any good, and you need to buy new injectors.

Final Considerations

Fuel injectors are one of the most important parts of the engine. When their work life comes to an end the driver will notice it in everyday driving. Shaking, problems with acceleration, and rough idling will make driving very difficult. 

Then some drivers will think about changing the fuel injectors alone. That is fine if they have some experience, but in most cases, it is best to leave this job to the pros. If the DIY change doesn’t go well the engine can have problems with fuel leaks. Fixing it is another issue, that the mechanic will tackle.

So, in this situation, it is better to pay a professional and get the job done, than to get into something that you are not sure about.