AutoCodes – GMC – P2002 GMC

P2002 GMC Code - Diesel Particulate Filter Low Efficiency

Quick Answer

The diesel exhaust aftertreatment system consists of an underhood pre-catalyst and an underbody catalyst. Common causes include Replace Diesel Particulate Filter (DPF). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P2002 GMC indicates Diesel Particulate Filter Low Efficiency.
Common causes: Common causes include Replace Diesel Particulate Filter (DPF).
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 1,173

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jul 26, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2002 GMC Description

The diesel exhaust aftertreatment system consists of an underhood pre-catalyst and an underbody catalyst. The underbody catalyst also consists of the main diesel oxidation catalyst and the coated Diesel Particulate Filter (DPF). One of the main purposes of the DPF is to collect particulates from the engine exhaust in order to minimize the discharge of soot to the atmosphere. The soot particles accumulate in the channels of the DPF and are burned off at regular intervals through a process called regeneration. This prevents the DPF from clogging. The Engine Control Module (ECM) commands the DPF regeneration after calculating various vehicle conditions such as DPF pressure difference, exhaust gas temperature, engine oil quality, engine speed, etc. Excessive accumulation of the soot in the DPF can cause a drop in the engine performance. During regeneration, additional fuel is injected via multiple post injections in order to increase the exhaust gas temperature. During this period, the DPF temperature is raised to approximately 600°C (1112°F) and the accumulated soot is oxidized or burned off into carbon dioxide (CO2).
The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the exhaust gas temperature at exhaust gas temperature sensor 4 is greater than 900°C (1652°F) for greater than 12 s.

OBDII Code P2002 GMC - Diesel Particulate Filter Low Efficiency - AutoCodes.com — P2002 GMC Code - Diesel Particulate Filter Low Efficiency

What does this mean?

What are the Possible Causes of the DTC P2002 GMC?

Replace Diesel Particulate Filter (DPF)

How to Fix the DTC P2002 GMC?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2002 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P2002 GMC Code

1. What are the common symptoms of OBDII code P2002 GMC (Diesel Particulate Filter Low Efficiency)?

- Common symptoms include reduced engine performance, decreased fuel efficiency, black smoke from the exhaust, and potential illumination of the Check Engine Light.

2. What are the typical causes of OBDII code P2002 GMC?

- The code is often triggered by a clogged or faulty diesel particulate filter (DPF), issues with the exhaust system, faulty sensors, or a malfunctioning regeneration process.

3. How can I diagnose the cause of OBDII code P2002 GMC?

- Diagnosis usually involves a thorough inspection of the DPF, exhaust system components, sensors, and the regeneration system. Using an OBDII scanner can help pinpoint the exact issue.

4. Can I continue driving with OBDII code P2002 GMC present?

- It is not recommended to drive with the code active as it may lead to further damage to the engine or emissions system. It is best to address the issue promptly.

5. How can I repair OBDII code P2002 GMC?

- Repair options may include cleaning or replacing the DPF, addressing any exhaust system issues, replacing faulty sensors, and ensuring proper regeneration of the DPF.

6. What are some preventive maintenance tips to avoid OBDII code P2002 GMC?

- Regularly servicing the vehicle, using high-quality diesel fuel, driving at highway speeds occasionally to aid DPF regeneration, and addressing any warning signs promptly can help prevent this code.

7. Does resetting the Check Engine Light resolve OBDII code P2002 GMC?

- Resetting the light may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to return. It's important to diagnose and fix the root cause.

8. Can a DIY enthusiast tackle the repair for OBDII code P2002 GMC?

- Depending on the skill level and access to tools, some DIY enthusiasts may be able to address simpler issues like sensor replacement. However, more complex problems may require professional assistance.

9. How long does it take to repair OBDII code P2002 GMC?

- The repair time can vary based on the specific cause of the code. Simple fixes like sensor replacement may take a short time, while more involved repairs like DPF cleaning or replacement can take longer.

10. Are there any recalls or technical service bulletins related to OBDII code P2002 GMC?

- It is recommended to check with GMC or a certified mechanic to see if there are any relevant recalls or technical service bulletins related to this specific OBDII code.