If you've recently purchased a used diesel vehicle after driving gasoline vehicles most of your life, you may be wondering about the different maintenance schedules you can expect with your new-to-you car. Today's diesel engines are highly fuel-efficient, largely due to the diesel particulate filter that helps reduce harmful environmental emissions from your engine. However, over time these toxins and contaminants can build up in your filter, affecting your vehicle's fuel efficiency and causing damage to the environment. When and how should you clean your diesel particulate filter to ensure optimum performance? Read on for more information about your cleaning and replacement options.
What is the diesel particulate filter?
If you've ever seen an older diesel truck or semi trailer emitting a huge cloud of black, smelly soot as it attempts to climb a hill, you know how dirty a diesel engine can potentially be. The diesel particulate filter, commonly known as the DPF, removes between 85 and 100 percent of the soot particles emitted by the use of diesel fuel. Not only does this filter help preserve the environment, it allows the engine to run at maximum efficiency, increasing fuel economy.
Because diesel engines can be dirty, most DPFs include some sort of self-cleaning mechanism -- otherwise, you'd need to take your diesel vehicle in for servicing every few hundred miles. Some DPFs are designed to periodically heat themselves to ultra-high temperatures by injecting and combusting gasoline, which burns off the soot into harmless ash that can slowly dissipate from your filter. Other DPFs require a chemical cleaning that can allow the soot to be removed by a technician and disposed of in an environmentally-friendly way.
However, after racking up tens of thousands of miles with a single DPF, you may find your DPF has built up an inner layer of soot and tar that cannot be easily burned off through the DPF's own self-cleaning mechanism. When this happens, you may notice you're not getting nearly as many miles out of a single tank of gas as you once did, or your engine may be lagging or running choppily, especially when you're going uphill or towing a trailer.
How should you clean a DPF?
Driving with a clogged DPF can eventually damage your filter badly enough that it must be replaced. To avoid this, you'll need to have it professionally cleaned. This can usually be accomplished by engaging in a larger-scale version of the DPF's own cleaning process. A technician will remove the DPF from your vehicle and place it in a cleaning chamber, where it will be heated to high enough temperatures to burn off any remaining ash. This ash will then be removed from your filter, leaving it as new and shiny as the day it came off the factory floor. You should be able to get a similar lifespan from your DPF before its next cleaning than you did from its initial "charge."
Is it ever worthwhile to replace the DPF rather than clean it?
Before scheduling an appointment to have your DPF cleaned, you'll want to check your vehicle manufacturer's specifications about the maintenance, repair, and replacement of the DPF. Certain types of DPFs may contain materials vulnerable to warping when heated to the high temperatures of a DPF cleaning machine, so you'll need to replace this DPF rather than having it cleaned. Cleaning the DPF without taking this into account could require you to spend money both for cleaning and later replacement. Fortunately, because these less heat-resistant DPFs have a shorter lifespan than more easily cleanable DPFs, they are available at a lower cost.