Engine Maintenance

Preventative maintenance is the key to keeping your truck running strong, and your diesel fuel injectors play a massive role in performance, fuel efficiency, and longevity. When injectors start acting up, you might notice rough idling, poor fuel economy, or even costly breakdowns. But here’s the good news—you can extend their lifespan and avoid major headaches with the right maintenance plan. In this guide, we’ll walk you through everything you need to know about protecting your remanufactured diesel fuel injectors so you can keep your truck performing at its best.

Can Diesel Fuel Injectors Be Rebuilt?

Yes, diesel fuel injectors can be rebuilt through a process known as remanufacturing. This involves completely disassembling the injector, inspecting each component, and replacing worn or defective parts with new ones.

Every remanufactured diesel fuel injector undergoes rigorous testing at DFC Diesel to ensure reliability. Key components like plungers, seals, valves, nozzles, and solenoids are replaced to restore full functionality. Remanufactured injectors are engraved or stamped for tracking, ensuring quality control and accountability. 

Want to learn more? Check out our diesel engine remanufacturing process to learn more about our diesel engine disassembly, cleaning, machining and assembly for each part.

How Long Should Remanufactured Diesel Fuel Injectors Last?

A properly remanufactured diesel fuel injector should last between 80,000 and 100,000 miles (about 150,000 km)—but that depends on how you drive, fuel quality, and how well you maintain your truck. If you tow heavy loads or use your vehicle for commercial work, your injectors will likely wear out faster.

The lifespan of a diesel fuel injector is tied to two core elements: fuel quality and component quality. A contaminated or low-grade fuel quality can accelerate the wear and tear on your injectors, which fail. Cutting corners on injectors might save you a few bucks upfront, but it could cost you more in repairs and fuel efficiency down the road. Are you looking to upgrade your fuel injectors? Check out our selection of remanufactured diesel fuel injectors for Cummins, Duramax and Powerstroke.

What are the Symptoms of Dirty Fuel Injectors?

If your diesel fuel injectors are about to fail, your truck will let you know. But what warning signs should you look for?  

• Fluctuating Power & Rough Idling – Inconsistent revs or engine vibration can signal a contaminated or failing injector.
• Misfiring on Startup – A clogged or malfunctioning injector can prevent proper fuel delivery.
• Reduced Fuel Economy – If your truck is burning more fuel than usual, inefficient injectors may be the culprit.
• Excess Smoke from Exhaust – White smoke could indicate poor fuel atomization or internal leaks.
• Fuel Odor—A crack in the injector seal or improperly closing valves can cause fuel to lead to noticeable smells.
• Stalling Engine – In severe cases, a failing injector may not deliver enough fuel, causing the vehicle to stall.

How Do You Prevent Remanufactured Diesel Fuel Injectors From Failing?

Want to get the most out of your fuel injectors? A little preventative maintenance goes a long way. Consider changing up your routine with a few easy steps:

• Use High-Quality Diesel Fuel – Poor fuel quality is one of the leading causes of injector failure. Always fill up at reputable stations to avoid contamination and water buildup.
• Turn Over Your Engine Regularly – If your truck sits for extended periods, start the engine periodically to prevent corrosion and fuel degradation.
• Use Fuel Additives & Lubricants – Diesel fuel treatments help keep injectors clean, reduce carbon buildup, and improve performance.
• Replace Injectors as a Set – Instead of swapping out a single failing injector, consider replacing the complete set. All cylinders experience similar wear, and replacing them together ensures balanced performance.

We take pride in our engines, starting with maintaining quality parts. If you want to upgrade your remanufactured diesel engine with performance parts for Cummins, Duramax and Powerstroke, we’re here to help. Contact us today to learn more about the best upgrades for your diesel engine.

Keep Your Diesel Injectors Running Strong with DFC Diesel

Your fuel injectors matter when keeping your truck running at peak performance. At DFC Diesel, we provide high-performance remanufactured diesel injectors designed for reliability and longevity.

Looking for the best upgrades for your engine? Contact us today to find the right remanufactured injectors for your truck and keep your engine running like new.

Diesel engines are renowned for their power and efficiency, but like any mechanical system, they can experience issues over time. When your engine is running smoothly, it can be easy to push off regular maintenance. The longer your engine goes without service, the higher the risk of engine failure. An early warning sign that your engine needs some TLC is when you experience a blow-by. Every type of engine is capable of engine blow-by, but high-performance engines and diesel engines will exhibit signs early on. Curious about why your diesel engine is experiencing blow-by? Let’s dive into the basics and diagnosis, and how to significantly reduce engine blow-by.

Why do Diesel Engines have Blow-By? Causes and Symptoms

Engine blow-by is a result of a mixture of air-fuel or combustion gases leaking between the engine’s pistons and the cylinder wall, escaping into the crankcase. This mixture typically consists of water vapour, carbon dioxide, unburned fuel, and air. Blow-by occurs when the pressure in the combustion chamber becomes too great to be contained, forcing these gases into the crankcase. It’s essential to understand that some degree of blow-by is normal, but excessive blow-by can signal underlying issues. To minimize risks to your diesel engine, it is important to periodically check the state of your piston ring seal and monitor any changes. 

Diesel engines, in particular, are more prone to blow-by compared to gasoline engines due to their higher compression ratios, which create greater pressure in the combustion chamber.

Common Causes of Diesel Engine Blow-By

• Piston Rings: Piston rings are crucial for creating a seal between the piston and the cylinder wall. Over time, as these rings wear down, the gap between the crankcase and the cylinder wall can increase, leading to increased blow-by.
• Worn Cylinder Walls: While piston rings bear the brunt of wear, the cylinder walls can also deteriorate. As they wear down, they create a larger gap between the wall and the piston, allowing combustion gases to escape.
• Scratching and Scouring: The core of your engine is just as susceptible to damage as any other part. Damage can be caused by dirt and debris caught in the cylinder, carbon in the oil, and leaking fuel injectors. Once the cylinder walls, pistons, and rings are damaged, it can create pathways for combustion gases to leak.
• High Carbon Levels: Considered the silent killer of diesel engines, carbon build-up in the piston ring grooves or engines without electronic fuel injectors can increase blow-by.
• Manufacturing Defects: In some cases, engine manufacturing defects, particularly in piston-to-cylinder clearances, or poor quality control, can lead to blow-by issues.

Engine blow-by can arise from a variety of factors and can easily be mistaken for other symptoms. However, understanding the symptoms of engine blow-by can help you plan and take preventative measures to protect your diesel engine and its inner workings.

During What Stroke Does Blow-By Occur in a Diesel Engine?

 Most diesel engines have a 4-stroke combustion cycle, with piston strokes for intake, compression, power and exhaust. Engine blow-by occurs when the combustion chamber hits the maximum pressure during the compression and power strokes. This reaction can be impacted by the engine temperature and whether or not it is under a load. The hotter the engine, the more likely it is to experience engine blow-by. 

As a rule of thumb, the average engine blow-by is between 1.5 and 3 cfm (cubic feet per minute) when the engine is hot and cold respectively.

What Happens to a Diesel Engine Experiencing Blow-By?

Are you trying to identify why your diesel engine is acting up? To help you rule out other factors,  knowing the signs of an engine blow-by can save you time and money and minimize the risk of a misdiagnosis. Is your diesel engine experiencing any of the common symptoms of blow-by?

• White Smoke: A telltale sign of blow-by is white smoke billowing from the oil-fill tube or valve cover opening.
• Rough Idling and Misfiring: Diesel engines experiencing blow-by may exhibit rough idling and misfiring, indicating a loss of compression in the combustion chamber. An engine misfire occurs when combustion gases escape early from the chamber.
• Increased Oil Consumption: If your diesel engine is using more oil than usual, it could be a result of blow-by contaminating the crankcase oil. Monitor your oil levels to ensure your engine will not seize and the timing of your oil change intervals.
• Excessive Exhaust Smoke: Blow-by can contribute to excessive exhaust smoke, which is often thick and discoloured.
• Poor Engine Performance: Overall engine performance may suffer, with sluggish acceleration and reduced efficiency. If you are experiencing reduced engine power, it can be a result of lost compression.
• Increased Fuel Consumption: Decreased engine efficiency as a result of engine blow-by can result in higher fuel consumption rates and increased expenses. 
• Runaway engines: In extreme cases of engine blow-by, your diesel engine can be at risk of running away and speeding out of control. If you notice any of the following symptoms, booking a service appointment should be your top priority.

How Do You Stop Blow-By in a Diesel Engine?

While it is nearly impossible to fully stop blow-by from happening, there are preventative measures you can take to mitigate the risk and ensure your diesel engine is in top condition. 

• Optimal Ring Seal: Ensure that the piston rings create a tight seal between the cylinder wall and the piston. Regular maintenance is critical for medium to heavy-duty diesel engines that operate at high pressures and temperatures.
• Ventilation: Use vent tubes or oil separators to manage extreme crankcase pressure and separate oil from combustion gases. Keep an eye out for a stuck-open valve, such as black smoke, engine sludge, or surging.
• High-Quality Engine Oil: Use high-quality engine oil and remove stiction from piston rings to maintain a tight seal.
• Regular Maintenance: Adhere to a strict maintenance schedule, including oil changes, injector replacements, and cylinder inspections. This will ensure that the pistons are more frequently monitored for signs of carbon buildup or contamination.

Did you know that you can improve your diesel engine performance and minimize engine blow-by with specialized parts? Consider adding a Speed of Air Hyperformance Piston to your diesel engine. DFC Diesel is committed to providing our customers with the highest quality parts to bring your vehicle to the next level. Check out our 5.9 Cummins, 6.7 Cummins, 6.7 powerstroke engine and other top-performance rebuilt engines.

The Speed of Air Hyperformance Pistons features a dimpled effect on the piston head to allow for a more complete combustion process, with fewer carbon deposits forming in the oil and the cylinder walls. Our products have been tested for medium-duty applications for Cummins engine, Duramax engines and Powerstroke diesel engines. Experience increased performance and savings with reduced fuel consumption and fewer oil intervals. Learn more about our Speed of Air Hyperformance remanufactured diesel engine series and request a quote today!