Best Injectors For 5.9 Cummins Common Rail

Off-Road Bandit TeamMar 18, '21

These devices evenly spray fuel into your engine so it fires with the most optimal mix of air and diesel fuel in your 5.9 Cummins. If your old injectors are kaput, here are some 5.9 Cummins common rail options that will make your truck perform like new.

5.9 Cummins Bad Injector Symptoms

Rarely do truck owners replace common rail fuel injectors, as the process is difficult for DIYers and novices. In most situations, 5.9 Cummins injectors are replaced due to telltale signs of failure.

But this isn’t a quality issue, rather just the fuel injectors reaching the end of their useful life. So before you get stranded somewhere, look for these 5.9 Cummins bad injector symptoms.

Engine Won’t Start

When the engine won’t start, several factors could be at play. But one of them is dead or clogged fuel injectors. 

Poor Fuel Economy

Your 5.9 Cummins relies on the perfect mix of air and diesel fuel to supply the best performance and fuel economy possible. So when a fuel injector starts to go bad, the ratio of fuel to air is adversely affected. This will cause your fuel economy to plummet to a noticeable level. If you’re constantly going to the pump, chances are you may have a bad/leaking injectors.

Rough Idling

If your vehicle is shaking while you’re idling, it’s another 5.9 Cummins bad injector symptom. Much like a misfiring injector will cause poor fuel economy, it will also cause sputtering due to the inefficient ratio of fuel to air. The result is your tachometer (RPMs) will start to flutter all over the place, as well as noticeable movement to the vehicle.

Review of the Best Injectors For 5.9 Cummins Common Rail

If you recognize any of the 5.9 Cummins common rail bad injector symptoms, you’re probably in need of a new fuel injector system. The good news is that you have plenty of options. So whether you’re searching for high-performance fuel injectors or you want a quality product on a budget, here are reviews of some of the best injectors for 5.9 Cummins common rail.

Best Overall: Industrial Injection Premium Bosch Injector: '04.5-07


  • Affordable price
  • One-year unlimited-miles warranty
  • OEM part for 5.9 Cummins
  • Built for premium performance
  • Noticeable upgrade in fuel economy


  • Difficult installation for novice DIYer

What Recent Buyers Report

Overall, the Industrial Injection Premium Bosch Injector delivers on all fronts, just as an OEM part should. Buyers report that the affordable price coupled with an uptick in both fuel economy and acceleration off the line as the foremost perks of this product. However, some users report that these failed after a short time, but it’s unknown whether this is due to faulty parts, poor quality, or improper installation.

Why It Stands Out to Us

If you want your 5.9 Cummins to run just like it did off the factory line, OEM parts are the way to go. And that’s just what you’ll get with these common rail fuel injectors. Add in a one-year warranty, and you’ll also get some comfort with your purchase.

Bottom Line

Affordable, straight from the OEM, and bringing peak performance, the Industrial Injection Premium Bosch Injector is a quintessential replacement for your original fuel injectors compared to other aftermarket options.

Runner-up: BD-Diesel CR Injectors +60-180HP: '04.5-07


  • Assembled to OEM standards
  • Each one calibrated for even, consistent flow
  • Made in Canada
  • Extrude-honed to provide more efficient fuel ignition
  • 24-month warranty


  • Expensive compared to other options
  • Not an official OEM part

What Recent Buyers Report

BD-Diesel CR Injectors are highly touted by buyers, with many reporting a great response to acceleration, power, and overall performance.

Why It Stands Out to Us

Assembled to OEM standards using computer-aided design and enhanced fuel atomization, these fuel injectors live up to the hype. Plus, they’re made in Canada and provide a 24-month warranty, alleviating the quality concerns that some Chinese-made products can cause.

Bottom Line

While thrifty buyers may want to look elsewhere for fuel injectors, buyers with the knowledge and affinity for a solid product should find that BD-Diesel CR Injectors are some of the best that money can buy. But for those that want an actual OEM part, Bosch fuel injectors may be the better choice.

Best for the Money: BD-Diesel Cummins Premium Injector: '04.5-07


  • Two-year warranty
  • Calibrated for perfect, consistent shot-to-shot operation
  • Improved fuel economy thanks to 60-hp operation
  • Built with Bosch parts
  • Adds to acceleration compared to OEM


  • Not a new part; remanufactured

What Recent Buyers Report

Recent buyers report that BD-Diesel Cummins Premium Injectors provide excellent performance in terms of acceleration, albeit with a bit more smoking from the engine.

Why It Stands Out to Us

Made from Bosch parts, these remanufactured fuel injectors work just like they’re brand new. And while some buyers may want a new product, the acceleration and boost in fuel economy paired with a two-year warranty prove that even remanufactured fuel injectors can check all the boxes of buyers.

Bottom Line

If you want high-quality fuel injectors without the brand-new price, you may not find a better product than the BD-Diesel Cummins Premium Injector. However, this may be off-putting for some other types of drivers, especially with the added smoking from the engine (although this is due to more fuel entering the cylinder than the OEM equivalent).

Editor's Pick: Industrial Injection 5.9L 24v Injector +40-150HP: '98.5-02


  • One of the most affordable options on the market
  • Some users report a boost to heavy towing/hauling
  • Provides a boost of up to 40 horsepower
  • Meets OEM fuel economy and emissions standards
  • One-year unlimited-miles warranty


  • Not Bosch branded; manufactured to Bosch specifications instead

What Recent Buyers Report

For the price, you won’t find a better option out there, according to many buyers of the Industrial Injection 5.9L 24v Injector. With a boost of up to 40 horsepower and excellent torque and acceleration, many buyers also report that these are a legit bargain buy. However, some users are off-put by the lack of Bosch branding and that it’s not an actual OEM part.

Why It Stands Out to Us

This product stands out because of one major aspect over others: price. With high-end fuel injectors, you may get solid results, but the price can cause some buyers to gasp, especially after the cost of installation. Plus, these injectors are manufactured to OEM standards, furthering its reputation.

Bottom Line

If you value a bargain buy, you probably won’t find a better value than the Industrial Injection 5.9L 24v Injector. But if the price isn’t your only determinant, you may want to look at Bosch/OEM parts or something that has more of a proven track record among 5.9 Cummins enthusiasts.

Honorable Mention: BD-Diesel 12v Cummins Set +45-120HP: '94-98


  • Comes in a full set for easy replacement
  • Five-hole nozzles for enhanced fuel atomization
  • Elbow fitting for more efficient fuel burning
  • 12-month, 24,000-month warranty
  • Flow-enhanced for improved fuel delivery


  • 12-valve only works on 1998 or older 5.9 Cummins

What Recent Buyers Report

Buyers report that BD-Diesel 12v Cummins fuel injectors provide an excellent 12-valve option that fits with old-school 5.9 Cummins vehicles.

Why It Stands Out to Us

For those that are holding onto their classic 5.9 Cummins truck, only the best parts will do. That’s just what this product provides. Offering a 12-valve setup accompanied with a one-year warranty, old-school 5.9 Cummins owners will love that this option is still alive and well.

Bottom Line

With five-hole nozzles and elbow fittings, the BD-Diesel 12v Cummins Set provides all six injectors in one complete package.

Benefits of Investing in a Quality Injector Set

While you’re most likely replacing your fuel injectors because of failure, you may also want to upgrade them for performance. Either way, you’re looking at plenty of benefits from a new system, even over a quality stock system.

Ideal Mix of Air and Fuel Compared to Stock Parts

Fuel injectors work with your vehicle’s onboard computer to create the perfect mix of air and fuel. And that’s just what a new, quality fuel injector set for 5.9 Cummins will do. With this proper blend, you won’t notice any rough idling or problems with fuel economy. Just excellent performance every time you get behind the wheel.

Smoother Drive

Without enough diesel in the cylinder, your 5.9 Cummins will certainly run poorly. However, a new fuel injector system will contribute to a better flow of diesel that allows the engine to fire properly. As a result, you’ll get a smoother drive, whether you’re commuting, idling, or putting the engine to the test on the highway or a straightaway.

Better Overall Performance

Another benefit of a fuel injector is better overall performance. While you may not notice a massive increase in torque, horsepower, or fuel economy—at least at first—fuel injectors have a pronounced effect on all three.

Don’t Inject Your Savings into Lackluster Systems for Your 5.9 Cummins Common Rail

Just like any other aftermarket part, not every product on the market is ideal for your 5.9 Cummins engine. So don’t inject your savings into something because it’s cheap or a name brand. Instead, do your due diligence, conduct the right research, and you’ll be satisfied with the purchase you make.

People Also Ask

Because bad fuel injectors are often misdiagnosed by amateur mechanics and 5.9 Cummins owners, many people have concerns about when to replace their fuel injectors. So whether you want to narrow down the cause of your vehicle’s problems or you just want to know more about common problems, here are some of the top questions people also ask.

How Do I Know if My 5.9 Cummins Has a Bad Injector?

As mentioned above, the most telltale signs of a bad injector in a 5.9 Cummins truck is rough idling, dancing of the tachometer (RPM needle), a quick, noticeable drop in fuel economy, or your engine won’t start at all.

Is It Bad to Drive a Diesel With a Bad Injector?

If you continue to drive a diesel truck with a bad injector, you don’t necessarily risk serious damage to your vehicle. Bad injectors won’t deliver enough gas for the engine to run, which can limit catastrophic damage such as that caused by running an engine without motor oil. However, the discomfort of sputtering, poor fuel economy, and other issues can cause most 5.9 Cummins owners to address the issue.

What Does a Bad Diesel Injector Sound Like?

Most often, a bad diesel injector sounds like a rod knock, which is a continuous rapping noise underneath the hood. You may also notice extra smoke when accelerating, as the diesel vehicle isn’t getting the right mix of fuel to support the sudden jolt of power.