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Regen in Progress: Can You Regen While Driving? (Answered)

Regen is a process in which it eliminates the health risk of our truck from soot build-up. To maintain a truck engine properly we need to do routine regens.

Sometimes, however, this process of regen can be too much of a hassle and we cannot always find suitable safe places to do a routine regen. What to do if we find ourselves in such situations?

Keep reading below as we discuss the different aspects of regen and if it is possible to do it while we drive or not.

What does Regen in progress mean? 

The message “regen in progress” appears in the multi-information display or MID of a vehicle it means that the DPF regeneration is in progress.

As a general rule of thumb, automatic DPF regen should take around 10-20 minutes and not more than that. Regeneration of a vehicle is all about removing particulate matter.

There are generally three different ways of regen. Furthermore, in two of the types of regen, it is rather done while driving and require no driver input. These are the active and passive regens. The third type of regen is the parked or forced regen.

DPF regeneration in progress:

This process of regeneration refers to the soot being burned away with a high temperature in the Diesel Particulate Filter (DPF).

The regeneration takes place automatically while we steadily drive the car, preferably on a highway. Most engines of a new car will actively regenerate DPF if the car is speeding above 40mph for at least 10-15 minutes.

DPR regeneration in progress:

Industrial vehicles of the Japanese manufacturer have a particulate filter system that is called DPR (Diesel Particulate Reduction).

In this process, it works in such a way that during normal use of the vehicle the particulates that are released by the engine will be retained by this filter. DPR regeneration takes approximately 15-20 minutes.

Can you regen while driving?

You can regen while driving. Ideally, your vehicle of yours needs to be running at operating temperature. If we take the car on a highway drive and drive as usual that will be the best. The exhaust outlet is going to give off readings of very high temperatures during active regeneration.

Regen is also known as the regeneration process. Where energy recovery happens by the means of technical processes. Whenever the conventional car stops, each of those time valuable energy is lost.

However, that’s only one side of regen being used in the vehicle industry. The other side of the regen word is the collection of soot and ash.

This type of regen has three distinct types of regen, where one is active, the other is passive and the latter is forced.

These days most of the newer vehicles can do a regen while driving. The process involves the soot within a diesel particulate filter in other words DPF is converted to ash with the use of chemical reaction, heat, and or electricity.

This happens because our diesel particulate filter, DPF undergoes routine passive regen as much as the needs while we have a casual drive.

However, we need to be driving steadily for the process to be complete. Active regeneration will give the best results during a highway drive.

How long does the regeneration cycle take on Volvo or Isuzu truck?

The process of making a Volvo truck to regen is checking the ATS status and making everything says “OK” and “N/A” then we can proceed with the parked regen for the vehicle.

It usually depends on the age of the vehicle to determine the time it will need for it to regen but none the less the approximate timing for it is usually 45-60+ minutes. The process continues to regen until the soot level reaches either “low” or “0%” on the MID.

In the case of an Isuzu truck, the optimal conditions for the engine to regen are having it parked with operating temperature, we press and hold the DPF switch for 3 seconds. This will start the regen process.

Certain precautions are needed to be taken in place when this process occurs. We cannot leave the vehicle, the power-take-off (PTO) should be turned off and never touch the DPF area since it will be very hot.

The regeneration cycle will take roughly 20 minutes to complete and the “regen in progress” message on the MID will be gone.

What happens if you stop a regen?

The basic principle of regen is not to stop it and let it go through the process of filtering all the particulates. However, if we do choose to let the process of regen stop and interfere, then the things that might occur are listed below.

Engine Shutdown:

Failure of regen will eventually lead to an engine shutdown. We need to pay attention to our “check engine light” in other words CEL as this may disable a DPF regen process sometimes.

Forced Parked Regen:

If we happen to skip or if we keep stopping a regen the car will force us to do a parked regen eventually.

Engine Derate:

If we do not complete a regen and make a lot of regen failures, this will ultimately lead the engine to derate and will be stuck there.

How long does a parked regen take?

Parked regen is a process where we park our vehicle and put it to selective or forced regen. Parked regen takes twenty minutes for some vehicles and sometimes it takes an hour and more for other vehicles. During this time the engine idle speed will increase.

Furthermore, it also depends on the age of a car too. If the car is brand new the process will take less time and if it is old, it will take more time. In general, the regeneration will not last more than 20-60+ minutes for most vehicles.

However, if the parked regen of your vehicle takes longer than expected then there must be something wrong with the vehicle. Promptly take the vehicle to a mechanic to get it looked at.

How do you know when parked regen is done?

When we start the parked regen system the car the engine idle speed increases. Furthermore, on the MID of the car, we will see either “regen on progress” or parked regen selective button will be emitting red light.

When the process of the regen is complete the engine idle speed will come down and the red light or the message on the MID will go away.

Only after that, we can start driving finally. It is strictly not recommended to start driving before we complete the regen process. Otherwise, the engine might shut down.

Can you do a forced regen while driving?

While it is possible to regen while driving if we want to force our car to do a “forced regen” then we need to follow a set of things.

First, we need to make our go into manual mode by moving the gear shift gently. We do not need to use the speed limiter.

Furthermore, we need to ride like this for at least 30 minutes. Finally, this will initiate a regeneration cycle. Thus, it will clean our DPF and that is how we can do a forced regen while driving.

How often should a truck regen?

The regeneration cycle of the truck is a necessary thing that cleanly burns off the excess soot that is usually deposited in the filter.

This in turn reduces the harmful exhaust emission that helps prevent the black smoke you often see coming out of the exhaust of diesel vehicles.

Therefore, a truck regeneration cycle is of vital importance. Depending on the fuel quality, engine oil type, idling time, and other factors can change the need of regen of a particular truck. However, a truck should regen once per tank of fuel.

What happens if you don’t regen a truck?

There are not many things that might happen if we do not regen a truck. The system is absolute and always reacts the same way regardless of what might cause us to not regen.

Derated Mode:

If we proceed to not regen our vehicle then eventually our vehicle will get stuck in a derate and that will then shut down the engine.

Active Regen:

This is a regen mode that happens when we do not regen a truck and this process initiates automatically. The truck does this active regen when it realizes that the amount of soot has reached the threshold.

Final thoughts

In general, a modern truck can undergo the regen process efficiently while driving easily. Furthermore, this often happens and is done by the DPF, the diesel particulate filter which goes into a passive regen when it deems necessary during steady driving.