Leaking Fuel Injector – Symptoms And What To Do

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Lately, your vehicle has been showing symptoms that there may be a problem with your fuel injectors.  You may be wondering how to tell if you have a leaking injector and what you can do about it! Since this could be a serious issue, we have thoroughly investigated and have found some answers for you.

A leaking fuel injector can and will have various symptoms, but the most common are:

  • Difficulty starting
  • Fuel odor in the vehicle
  • Hesitation or shaking while idling
  • Increased fuel consumption
  • Failed emissions test
  • Increased exhaust

When you see signs that your fuel injector is leaking, you may need to replace the fuel injector itself, or in most cases, just the o-ring.

Now that you know what to look for to determine if your fuel injectors have begun to leak, you may have more questions. Keep reading as we discuss what causes a leak, how to fix it, and how much you may have to invest!

Car mechanic fixing fuel injector at two camshaft gasoline engine, Leaking Fuel Injector - Symptoms And What To Do

What Causes A Fuel Injector To Leak?

Though fuel injectors generally hold up for the life of the engine, driving habits, along with poor maintenance, can contribute to failure. Leaking fuel injectors are more common in older cars with high mileage.

Experts say that there are usually two main ways that a fuel injector can leak. Either from the body of the injector itself or an O-ring.

If the damage is to the injector itself, such as corrosion or a crack, the injector will need to be completely replaced. This type of leak can be from damage to the body, pintle, ball, or disc seat of the injector. Rough driving with hard stops and starts can cause damage that can contribute to this type of leak.

A leak from an o-ring can be caused by ill-fitting, brittle, or damaged o-rings. Leaks of this type are caused by the age of the o-rings and poor maintenance, causing parts to corrode, become brittle, and break down over time.

Can You Drive With A Leaking Fuel Injector?

A driver is drifting on his car in sharp turn

Since a leaking fuel injector can cause issues with starting your vehicle, it may not be possible to drive your car, depending on the severity of the leak.

Leaked fuel can heat up on your engine and can combust. It can also cause further damage to your vehicle, such as a hydro-locked engine. If your car is driveable, yet you notice the symptoms of a faulty fuel injector, we recommend not driving and addressing the issue as soon as possible.

Will A Bad Fuel Injector Throw A Code?

The first step you should take to address your leaking fuel injector is to confirm that this is indeed your problem! Since a leaking fuel injector may throw a code or show up on a test, different devices can help you pinpoint the faulty injector.

OBD2 Scanner

This diagnostic tool can be plugged into your vehicle whether you see a check engine light or not. Since it works by reading error logs saved in your vehicle’s computer, It’s great to have for owners of older cars and can even save you money and time by giving you a general idea of the issue before going to your mechanic.

A bad fuel injector may throw a misfire code. Check the misfire screen to tell you which injector is causing the problem. These codes will start with P02.

Since a leaking fuel injector can cause a failed emissions test, use this device to check those results as well!

Click here to see this OBD2 Scanner on Amazon!

Fuel Injector Tester

This device is specifically used to test your injectors. It can show issues caused by leaking, corroding, and clogging. Since it comes with cleaners as well, it’s great for DIY maintenance.

This fuel injector tester works with the engine off and can be used with a fuel pressure tester if needed.

Click here to see this Fuel Injector Tester on Amazon!

How Much Does It Cost To Fix A Leaking Fuel Injector?

Once you determine which injector is faulty and what route you will take to address your situation, you will then need to find out the cost to fix it. Quotes vary greatly on replacement and parts since it’s specific to who is repairing, the type of vehicle you are repairing, and location.

Can You Replace Just One Fuel Injector?

Experts agree that if you need to replace one fuel injector, it is best to replace them all at the same time. If the injector needs to be replaced, you can expect to pay anywhere from $250-$1500. When you get the quote from your mechanic, ask if the quote includes parts and labor.

If you are vehicle repair savvy and are familiar with the basic anatomy of your fuel system, you may be able to do the replacement yourself. You would save money and only pay around $150 to $600 for the injectors.

Consult your car manual to see which type you need for your vehicle or filter your results on a site like Amazon to get the parts needed for your car or truck.

This is an example of a replacement kit that would be used for a 2006-2018 Chevy, Buick, GMC, or Cadillac. 

Click here to see this example of a fuel injector kit on Amazon!

Replace The O-Ring On A Fuel Injector

A faulty o-ring causes the majority of leaking fuel injectors. Often the whole injector is replaced when all that was needed was to replace the O-ring. They are less expensive! When paying for o-ring replacement, your costs will depend more on local pricing since most of the cost will be labor. 

Experts estimate around $30-$75 for parts on average plus your local rate for 2 hours of labor to calculate the cost.

If you know your way around your vehicle, you can also do this yourself! If you replace one, we recommend replacing all the o-rings since the injectors are all held in place by the same rail. It will make future maintenance easier since your parts will have the same wear and tear. 

Consult your vehicle manual to see what type of engine you have to find out what type of o-ring kit you should purchase. You can also see if the O-ring you are looking at will fit your vehicle by using the checker at the top of any Amazon page for vehicle parts. 

See this example of an O-ring kit on Amazon!

Prevent Future Leaking Fuel Injectors

Now that you know the symptoms you should look out for to diagnose your fuel injector issues and what you can do about them, you can now decide whether to fix the leak yourself or get a mechanics quote.

Popular advice is that your fuel system should be checked and cleaned every 3,000 miles. Regular cleanings and maintenance will stop clogged injectors from turning into a more serious problem and keep your injectors working for years to come!

See this fuel injector cleaner on Amazon!

See this fuel injector nozzle flush on Amazon!

Read the following articles for more information on maintaining your vehicle!

“5 Best Engine Oil Additives for Reducing Engine Noise”

“7 Of The Best Oil Additives For Older Engines”

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