P2002: Diesel Particulate Filter Efficiency Below Threshold Bank 1

When you see trouble code P2002, there’s an issue with the backpressure of your emissions system. This pressure is caused by your diesel particulate filter, or DPF. So, how do I fix trouble code P2002? Learn how this soft code may resolve itself and how to check for signs of damage and find the right solutions to restore your vehicle.

What Does P2002 Mean?

Your diesel engine emits soot under normal operations. In order to filter 98% of the soot emissions, your diesel exhaust includes this innovative filter. It uses metal fibers, silicone carbide and cordierite to coat a matrix of passageways and create a long-lasting filter.

Over time, your filter can become clogged with soot and other debris. Your vehicle’s engine control unit monitors the level of backpressure to determine whether the filter is allowing the correct amount of emissions to pass through. Once it’s determined the filter is operating below the preset threshold, it triggers trouble code P2002.

Unlike many trouble codes, P2002 is a soft code. This means that it will update continuously and clear the code once the issue is resolved. Unless there’s an issue in the electrical system, you can expect this code to be solved without your help. However, it’s still important to check for other issues, as these other causes can damage your engine and reduce your vehicle’s performance.

What are the Symptoms of P2002?

You may experience a reduction in your fuel economy. Because your diesel engine has features that help manage this trouble code without external assistance, your exhaust temperature will increase while this error code is present.

Another symptom is a dilution of your engine oil. This could help you solve the clog in your filter but will also shorten the service life of your oil. You may experience some performance issues, such as a slow acceleration during your OBD-II scanner error code P2002 problem.

Common Causes

Your diesel needs to routinely operate between 500c and 600c for your DPF to operate efficiently. If you continue to drive at slower speeds, your filter may collect too much soot. Another common cause is an air leak forward of the DPF. A large enough leak and affect the air pressure and trigger the sensor, even if your DPF has no issues.

Most often, trouble code P2002 is a result of a clogged DPF. You’ll simply need to burn off some of the soot to clear the filter and restore its functionality. Of course, there are many other reasons that this error code could be triggered. A damaged sensor, air leak, or damaged DPF could all be causes. Unlike soot buildup, these problems won’t be resolved by your engine. Allowing your engine to dilute your oil and run at higher temperatures over a long period of time could reduce the effectiveness of your oil and cause other issues.

Typical Solutions

Most error code P2002 issues are temporary. Your engine is designed to adjust the temperature and oil dilution as necessary to combat this clog. Soot buildup should clear up quickly, so the issue may resolve itself.

However, it’s important to visually inspect your differential pressure sensors and your DPF. Look for any electrical damage, such as frayed or loose wiring. If you can’t find another issue, bring your engine to 1,400 RPMs for up to 20 minutes in a safe setting. This should create the right temperature to burn off any soot clogging your filter.

Now that you’ve gone through all the common causes and typical solutions, you can finally answer, what does the code P2002 mean? Carefully inspect every area to ensure that your diesel is safely filtering out harmful soot emissions and operating at peak efficiency.

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