The Top Signs Your Exhaust And Aftertreatment System Needs Repair

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Iron Buffalo Truck & Trailer
September 15, 2023
The Top Signs Your Exhaust And Aftertreatment System Needs Repair

With the advent of advanced aftertreatment systems, heavy-duty truck emissions have lowered substantially over the past decade. Harmful exhaust fumes are now filtered through countless catalysts, from the Diesel Particulate Filter (DPF) to the Selective Catalytic Reduction (SCR) system. Without these technologies, your truck’s emissions wouldn’t pass DOT inspections, let alone EPA standards.

Your heavy-duty truck's aftertreatment system is integrated with its aftertreatment system. Like any other complex system in your truck, these two units need tender loving care to ensure safe operation, legal compliance, and optimized performance. In this article, we’ll be taking a look at the top signs your exhaust and aftertreatment system need repair.

Signs Your Exhaust & Aftertreatment System Needs Repair

Keep an Eye on the Warning Dash Light

When a warning light illuminates on your truck's dashboard, it's a clear indicator that either your aftertreatment system or exhaust requires immediate attention. There are a few things you have to pay close attention to, like the HEST lamp, DPF lamp, DPF regeneration cycle, DEF lamp, and the classic check engine light. These lights reveal irregularities within the aftertreatment system or exhaust, particularly its struggle to reduce harmful emissions from the engine's combustion system. Don't disregard these warning beacons, as they could save you from expensive repairs down the line. Stay vigilant and address any issues detected by the dashboard warning light promptly.

Low Engine Power 

If your heavy-duty truck starts losing power and struggles to accelerate, it's a sure sign that something is amiss—particulary when climbing steep inclines, your truck's reduced performance can become evident. To restore its power, downshifting to a lower gear can provide a much-needed boost. By increasing the engine's RPM, you provide more torque for your truck to help climb challenging terrains. Failing to downshift could lead to overheating or even engine failure, posing risks to both your vehicle and other road users. Common causes of low engine power include a clogged exhaust and aftertreatment system, fuel system issues, or blockages in the engine components.

Poor Fuel Efficiency

Monitoring your heavy-duty truck's fuel consumption is crucial for cost efficiency. If you notice a significant drop in miles per gallon, it's a sign that your exhaust and aftertreatment system may be failing and in need of repair. Factors such as underinflated tires, worn-out piston rings, or a malfunctioning fuel injector can also contribute to poor MPG. Keep an eye on the exhaust system's condition as it directly affects your truck's gas mileage.

Exhaust Smoke

Unusual smoke emitting from your heavy-duty truck's exhaust is often an indication of engine or aftertreatment system issues. Different colors of smoke provide clues to the underlying problems:

  • Black Exhaust Smoke: Sooty residue from the tailpipe suggests a malfunctioning aftertreatment system or engine, indicating excessive fuel consumption or a clogged diesel particulate filter. A thorough inspection is necessary to identify the exact cause, which could involve components such as the oxygen sensor, fuel injector, or turbocharger.
  • Blue Smoke: Blue smoke signifies burning oil, indicating potential faults in valve seals, piston rings, or the turbocharger. A careful examination of these components is essential to rectify the issue.
  • White Smoke: White smoke indicates vapor from burned coolant in the engine, which may be a result of a cracked cylinder head, damaged head gasket, broken EGR cooler, or condensation during cold weather. Coolant leaks into the engine's combustion chamber sor exhaust can cause harm to the aftertreatment system, necessitating immediate attention.

Coolant Loss Without External Leaks

If you notice a decrease in coolant level without any visible external leaks, it could be an internal leak into the engine's combustion chambers or exhaust system. This type of leak can also affect the aftertreatment system, causing the deterioration of its components. Keep an eye out for white steam or smoke emissions from the exhaust, as it may indicate EGR cooler failure or other coolant-related issues.

Intake Leaks

Intake leaks pose a significant risk to the exhaust and aftertreatment system's functionality. Such leaks disrupt the balance of exhaust gases, impacting the engine's combustion efficiency and the aftertreatment system's ability to reduce harmful emissions. Ensuring a proper air-fuel ratio is crucial for optimal performance and compliance with emission regulations. Intake leaks can lead to clogged DPFs and hinder successful passive regeneration processes, which may ultimately damage the aftertreatment system.

Clogged Air Filter

A neglected air filter can introduce contaminants into your heavy-duty truck's engine, impairing its performance and affecting the aftertreatment system's effectiveness. A clogged air filter restricts diesel flow through the exhaust, reducing engine power and causing harmful emissions. Regularly replacing the air filter is essential in maintaining the proper functioning of the exhaust and aftertreatment system.

Irregular Engine Noises

Pay attention to any irregular engine noises, as they may be indicative of exhaust and aftertreatment system issues. Unusual popping or rattling sounds could signify damage or a loose exhaust pipe. Seeking the expertise of a trusted mechanic to inspect and address these noises is crucial to prevent further damage and maintain optimal system performance..

Final Words

If you want to extend the life of your heavy-duty truck’s exhaust and aftertreatment system while avoiding expensive repairs, it’s important you stay attentive to warning lights, decreased engine power, poor fuel efficiency, exhaust smoke, coolant loss, intake leaks, clogged air filters, and irregular engine noises. Promptly addressing these problems through proper maintenance and repair will not only help protect your bottom line but also ensure the efficient and eco-friendly operation of your vehicle. If you need a reputable partner for your exhaust and aftertreatment system repairs, contact JE-CO Truck & Trailer Repair today.