What is a passive regen?

Passive regeneration is an approach used to oxidise particulate matter (PM) in the diesel particulate filter (DPF). In contrast to higher temperature active regeneration, passive regeneration uses normal exhaust temperatures and nitrogen dioxide (NO2) as the catalyst to oxidise PM in the DPF.

What is the difference between active and passive regeneration?

Active regeneration involves raising the actual exhaust gas temperature by introducing additional thermal energy. In contrast, passive methods are based on lowering the required temperatures to a range within which the available temperature is adequate for regeneration.

How long does a passive regen take?

The vehicle operator must set the park brake and enable the parked regeneration to begin. Engine rpm increases and raw fuel is injected into the exhaust gas at the exit of the engine to generate the appropriate regeneration temperatures. The stationary vehicle manual regeneration processes take about 30 minutes.

What are the three types of Regen?

As mentioned earlier, there are three types of DPF regeneration: passive regeneration, active-only regeneration, and passive-active regeneration. Proper maintenance of the DPF is essential to prevent clogging and maintain the engine's performance and fuel efficiency.

What temperature should passive regen be?

Passive Regeneration. Thermal regeneration of diesel particulate filters requires temperatures of around 600°C (Figure 1). Such exhaust temperatures are rarely encountered in practical applications of the diesel engine. Most heavy-duty diesel engines produce exhaust temperatures in the range of 300-450°C.

#05 What is passive regeneration?

Can a regen damage an engine?

In these cases, a forced regen is required and a driver has to pull over and wait while the DPF completes a more rigorous self-cleaning process. Failure to perform a forced regen when notified by your vehicle's indicator system can cause severe engine damage.

What are the different types of DPF regeneration?

How do I maintain a diesel particulate filter? The best way to maintain a DPF is to make sure it's fully able to regenerate itself when it's full of soot (when the warning light appears). There are two types of regeneration: passive and active.

How to do passive DPF regeneration?

Passive regeneration is another way in which your DPF is designed to empty itself. In order to trigger passive regeneration, you need to take your car for a longer drive, so that the exhaust can reach a higher temperature.

What speed does DPF passive regenerate?

Passive Regeneration

Driving at 70mph or above for a while will heat the exhaust enough to burn off the soot particles which have been trapped by the DPF.

Can I drive while my truck is doing a regen?

The vehicle needs to run at operating temperature during the regeneration, so highway driving is best. Just drive as you normally would. During active regeneration, the exhaust outlet temperature is extremely high.

What happens if you stop a regen early?

Regeneration, or regen, of the DPF filter, is the process that burns the soot accumulation that is inside the DPF filter. If you can no longer start a regen then you will eventually get stuck in a derate which will then lead to an engine shut down.

How many times can a DPF be regenerated?

Active regeneration will be initiated every 300 miles or so depending on how you use your car and will take 5 to 10 minutes to complete. But it's a problem if your journey's too short and the regeneration doesn't finish. During active regeneration you may notice: Cooling fans running.

Why is my truck asking for a regen so often?

Regen problems generally arise where city driving, excessive idling or light duty cycles are encountered. Or, if other engine components such as EGR valves, turbochargers, injectors are fouled or not working properly. DPF regeneration cycles then become more frequent, and more prolonged!

Can you drive during a regen?

An automatic regen does not require any action by the driver, other than making sure the truck stays ON. It is safe to continue driving as normal. A regeneration cycle typically takes between 10 and 30 minutes to complete.

What happens if regen takes too long?

If your forced DPF regen lasts closer to an hour or continues beyond that, it likely suggests that your exhaust temperatures are not building up high enough to successfully burn off the soot collected in the DPF and that the truck is still trying to bring down those soot levels.

What is the longest a regen should take?

On average, it takes between thirty and sixty minutes to complete a forced regeneration. The substantial heat required for the regen renders the engine and aftertreatment system untouchable until it has time to cool down.

Does regen use more fuel?

Active DPF regenerations need to burn extra fuel to achieve the high exhaust temperature for soot oxidation, which results in the increased fuel consumption rates.

What is the most powerful of regeneration?

Lizards possess the highest regenerative capacity as a group.

How do I stop my DPF from clogging?

How can I clear my DPF by driving?

The easiest and cheapest method of DPF filter cleaning is by driving the vehicle for a long-distance at high revs per minute. Doing this increases the heat of the exhaust and burns the soot blocking the DPF filter. It's best to drive on a motorway or A road where you can keep the vehicle at a consistent speed.

Can I drive with exhaust filter full?

Technically yes, but we would not recommend it. If you ignore the DPF light and continue driving, the build-up of soot will soon reach a point whereby your car has to enter 'limp-home' mode in order to prevent any damage to the engine.

How do you know when parked regen is done?

Wait for the regeneration to start. Monitor the Exhaust temperature and RPM. When the idle comes back down it means that the regen has finished. If the regen starts and stops then you may have a problem that prevents the regen from taking place.

How many times can a DPF be cleaned?

For on-highway vehicles, the DPF should be pulled off for its first cleaning after 150,000 to 200,000 miles, and then every 100,000 miles after that for preventive maintenance cleaning, Anderson notes.

How do I know if my DPF is regenerating?

So how do you tell that your engine is performing an active DPF regeneration? One signal to look for is your cooling fans running at a higher capacity than normal, or the sound of your engine may change note. Sometimes, a hot and pungent smell can also start coming from your engine as the soot is being burned away.

Can a DPF regenerate on idle?

Even at low engine speeds particulates are emitted by your engine, so keeping your engine ticking over when you're parked or not moving can clog your filter quicker, because DPF regeneration cannot occur at idle.