Why Does My Truck Regen So Often? Causes and Solutions

“Why does my truck regen so often?” is a common question among truck owners. Although regeneration is important in controlling emissions, forced regenerations are not.

A clogged DPF filter is the most common reason a truck regenerates frequently. This article explains the reasons behind forced regeneration and how to fix the problem.

Why Does Your Truck Regenerate So Often?

Your truck regenerates so often because of a clogged DPF filter, defective sensors, and clogged fuel filters. Excessive idling, heavy hauling, and a malfunctioning exhaust system also contribute to this problem.

It is important to diagnose the root of the problem and have it checked by an expert immediately.

– Clogged DPF Filter

Also known as Diesel Particulate Filters, they store exhaust waste and contaminants, reducing emissions from your diesel engine. The DPF is located in the car’s exhaust system and cleans itself by regenerating.

Over time, it becomes clogged with buildup soot, dust, or grime. In this case, a regular regeneration may not be enough to burn the soot.A forced regen cycle is required to clean the DPF thoroughly, but this tends to happen unexpectedly.

Aside from unexpected DPF regens, a smoky exhaust system is another symptom of a clogged DPF. You’ll also notice a reduction in fuel economy, a burning smell, and a general loss of power.

You can tell when a DPF cycle occurs if you notice an increased downtime and fuel consumption. Your cooling fans may start to run, and your idle speed may increase. You may also notice a burning smell from your exhaust system.

– Prolonged Idling

If you’re wondering, “why does my truck regen so often?” it may be due to excessive idling. When you idle for long periods, it adds unnecessary strain to your engine.

Prolonged idling also increases vehicle emissions and causes a clogged DPF. If you drive short distances, the exhaust gas temperature (EGT) is significantly lower than when you drive long distances.

A low EGT increases the amount of unburned fuel and soot entering the exhaust system. If your EGT isn’t high enough to burn off the soot before reaching the DPF, a forced DPF regeneration will occur. A forced regeneration will increase downtime and fuel consumption.

– Dirty Air Filters

Dirty air filters are another reason why your truck regens so often. If dirt has clogged your air filters, it will surely affect the performance of your DPF. An air filter can become clogged with dirt, tiny particles, debris, grime, and other contaminants.

When this happens, it disrupts the right airflow from getting into the vehicle’s engine. If there’s a significant change in the air-fuel ratio needed for combustion, the cylinders won’t be able to process the mixture well.

This increases the rate of emission, which can clog the DPF with time. Besides inducing forced regens, a dirty air filter also reduces gas mileage. Acceleration becomes poor; the engine may misfire or stall, and unusual noises become frequent. Your check engine light may come on as well.

– Clogged Fuel Filters

A clean fuel filter is also as important as a clean DPF. A fuel filter is responsible for keeping fuel running in the engine. If a fuel filter becomes clogged with dirt or debris, it introduces an inappropriate amount of fuel into the engine.

A clogged fuel filter often causes your engine to misfire, leading to soot and carbon buildup. Continuous misfiring will increase accumulation until a passive regen cycle can’t clean the DPF. In this case, your truck’s ECU will induce forced regenerations to completely clean out the DPF.

– Heavy Hauling

Heavy hauling is also a common reason why your truck regens frequently. When a truck is used to tow heavy loads, it can damage the exhaust system. This happens when the heavy loads cause the exhaust to drag on the ground, leading to total failure.

When the exhaust is damaged, there will be an excess buildup of soot and ash, which can clog the DPF, especially when the engine misfires. In this case, your truck will frequently regenerate because it is trying to eliminate the excess soot.

– Damaged DPF Differential Pressure Sensor

Another reason forced regeneration occurs easily is that your DPF sensor is damaged. The DPF sensor, known as the Differential Pressure Sensor, is responsible for the smooth functioning of the DPF.

It measures exhaust back pressure and controls when the ECU should activate the particulate filter regeneration. The DPF differential pressure sensor can become damaged due to bad wiring, as well as clogged or corroded sensor hoses.

In this case, your DPF may regenerate more often in reaction to the damaged differential pressure sensor. You may also notice a fuel economy reduction, poor engine performance, increased emissions, and high transmission temperature.

– Driving in Cold Weather

A lower exhaust gas temperature (EGT) makes it harder for DPF to burn off the soot. Hence, driving in cold weather can cause your truck to regen frequently.

This is because there isn’t enough heat to burn off the soot, and continuous driving in such weather will increase soot buildup. If it gets to the point where your DPF cannot burn off the soot, a forced regeneration will happen to clean it up.

What To Do if Your Truck Regens Too Often?

If your truck regens too often, you can reduce how often forced regeneration happens by cleaning your DPF and air and fuel filters. You should also combine grips, replace DPF differential pressure sensors, and avoid heavy hauling. Finally, regular maintenance will prevent any future reoccurrence.

So how often should your truck perform a regen?

A functional truck can experience a regeneration daily, weekly or monthly. It all depends on the truck’s duty cycle and how well it is being maintained. Trucks used for heavy hauling or highway driving may regen more often than trucks that travel short distances at low speeds.

– Clean Clogged DPF

You can eliminate the issue of forced regeneration by cleaning your DPF. You can do this yourself or leave it to a professional mechanic. If you decide to clean the DPF yourself, you should be careful when removing and cleaning the filter. A Diesel Exhaust Fluid comes highly recommended to help break down soot and carbon buildup in the filter.

Aside from cleaning DPF, remember to use high-quality fuel for your truck. Quality fuel reduces the rate of exhaust emissions, leading to less soot accumulation.

What will stop normal regeneration from occurring? Shorter trips, low speed, and a low exhaust gas temperature can stop normal regeneration from occurring. When these factors become the predominant duty cycle of your truck, the DPF will be unable to perform properly.

– Combine Trips

Short trips are a big problem that can force regens, so you should combine trips. Longer trips reduce excessive idling and increase the exhaust gas temperature. Hence, the EGT becomes high enough to burn off the soot and other residual particles. You should also spend more time driving on the highway.

 

Increased speed also aids the DPF in burning off soot and ash from the exhaust pipe. Longer trips and higher speeds will reduce the frequency of regeneration that occurs when you drive your truck.

– Clean Dirty Air Filters

Another quick solution to reduce how often your truck regenerates is to clean your air filters. Cleaning an air filter is simple and doesn’t require a mechanic. You must first turn off your engine and wait about 30 minutes.

Then, locate the car’s air filter and remove it from its compartment. Apply an automobile cleaning solution and let it sit for about 10 to 15 minutes. After doing that, rinse off the air filter with a water hose till it is clean.

Let the filter dry for some minutes before oiling it if needed. Before replacing it, check the surrounding areas and clean off visible dirt and debris. A clean air filter should eliminate the issue of forced regeneration.

– Clean Clogged Fuel Filters

Cleaning your clogged fuel filters can stop your truck from regenerating frequently. You can clean a clogged fuel filter almost the same way as an air filter. However, this may require more caution and precision. We advise you to consult a professional mechanic to help clean the filters.

After cleaning the fuel filter, you should inspect the fuel injectors and pump to ensure those are also in good working condition. Always remember to lubricate these parts with oil to avoid corrosion and rust.

– Avoid Heavy Hauling

Avoid heaving hauling if you want to reduce the rate of forced regeneration. Since a heavy load can cause your exhaust component to crack, avoid hauling a heavy load. If you must, stay within the truck’s towing capacity. That way, your exhaust system remains intact, allowing the DPF to clean itself easily.

– Repair or Replace the Differential Pressure Sensor

If the DPF’s differential pressure sensor is spoilt, you must repair or replace it immediately. Replacing the differential pressure sensor requires a high level of technical expertise.

It is best to contact a professional mechanic or auto repair shop to carry out this task. Depending on the vehicle brand and model, a differential pressure sensor may cost between $80 and $150 to replace.

– Avoid Long Driving In Cold Weather

Since cold weather can significantly reduce the exhaust gas temperature, you should avoid driving in such conditions. If you must drive in cold seasons, driving for long hours and on the highway is best. This gives the DPF enough heat to burn off the soot and other contaminants.

Frequently Asked Questions

– How Long Does a Regeneration Usually Take?

Regeneration usually takes between one to three hours. However, it depends on how well a truck is maintained. A functional truck that is well maintained will require less regeneration time compared to an old or fault-ridden truck. Hence, there is no clear-cut answer to how long this process will take.

– What Is the Price of a New DPF?

The price of a new DPF varies between $350 and $800. However, this depends on the brand and model of the truck you drive. You should note that the labor cost may or may not be included in the price range.

– Can You Disable Regeneration on Your Truck?

You will be able to disable regeneration on your truck depending on what type of regeneration and exhaust system your truck uses. Some vehicles allow users to disable the regeneration feature, while others don’t. You will have to check if your truck supports this feature before attempting it.

– Is It Possible To Drive Without A DPF?

Yes, it is possible to drive without a DPF in your truck. However, this is unadvisable because it increases the release of harmful gasses into the air, causing environmental pollution. It also inherently causes damage to your engine due to a buildup of carbon.

Conclusion

Now that you can identify the reasons behind forced regeneration, you know the right steps to fix the problem.

Here is a quick summary of the main points discussed in this article:

• Why does your truck regen so often? Your truck often regens because the DPF filter is clogged. A clogged fuel and air filter, prolonged idling, and a damaged differential pressure sensor can cause this.
• You can fix this problem by cleaning your DPF, air, and fuel filters. Repairing your sensor, taking long drives, and avoiding cold weather is also a great way to reduce forceful regeneration.
• You should always contact a professional mechanic for proper diagnosis and repairs.

Forced regenerations can be problematic but also easy to fix. With all you’ve learned in this article, you should be able to identify the cause of a forced regeneration and fix the problem immediately.