AutoCodes – GMC – P140C GMC

P140C GMC Code - Exhaust Gas Recirculation Slow Response Decreasing Flow

Quick Answer

The Exhaust Gas Recirculation (EGR) valve is an electrically controlled valve that is controlled by the Engine Control Module (ECM). Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection. 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: P140C GMC indicates Exhaust Gas Recirculation Slow Response Decreasing Flow.
Common causes: Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection.
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 15,121

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 25, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P140C GMC Description

The Exhaust Gas Recirculation (EGR) valve is an electrically controlled valve that is controlled by the Engine Control Module (ECM). The EGR allows a specific amount of your exhaust gas into the intake manifold. This exhaust gas mixes with the intake air and cools the combustion process. The recirculated exhaust gas also prevents the formation of nitrogen oxides (NOx). The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the actual EGR flow is lower than a calibrated value for greater than 5 s.

OBDII Code P140C GMC - Exhaust Gas Recirculation Slow Response Decreasing Flow - AutoCodes.com — P140C GMC Code - Exhaust Gas Recirculation Slow Response Decreasing Flow

What does this mean?

What are the Possible Causes of the DTC P140C GMC?

Faulty Exhaust Gas Recirculation (EGR) Valve
Exhaust Gas Recirculation Valve harness is open or shorted
Exhaust Gas Recirculation Valve circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P140C 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 P140C 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.

Need more information about the P140C GMC code?

Need more information on how to fix the P140C GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

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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 P140C GMC Code

1. What are common symptoms of OBDII code P140C GMC (Exhaust Gas Recirculation Slow Response Decreasing Flow)?

Symptoms may include rough idling, engine hesitation, decreased fuel efficiency, and a noticeable decrease in engine performance.

2. What are the possible causes of OBDII code P140C GMC?

The code P140C usually indicates issues with the Exhaust Gas Recirculation (EGR) system, such as a faulty EGR valve, clogged EGR passages, or a malfunctioning EGR temperature sensor.

3. How can I diagnose the cause of OBDII code P140C GMC?

Diagnosing the issue involves inspecting the EGR valve, checking for carbon buildup in the EGR passages, testing the EGR temperature sensor, and ensuring proper EGR function.

4. Can a dirty or clogged EGR valve trigger code P140C GMC?

Yes, a dirty or clogged EGR valve can restrict the flow of exhaust gases, leading to a slow response and triggering the P140C code.

5. What are some repair tips for addressing OBDII code P140C GMC?

Repair options may include cleaning or replacing the EGR valve, clearing any blockages in the EGR passages, testing and possibly replacing the EGR temperature sensor, and ensuring proper EGR system function.

6. Is it safe to continue driving with OBDII code P140C GMC?

It is generally not recommended to continue driving with this code active, as it can lead to decreased engine performance and potential long-term damage if left unresolved.

7. Can a malfunctioning EGR temperature sensor cause code P140C GMC?

Yes, a malfunctioning EGR temperature sensor can disrupt the EGR system's operation, leading to slow response times and triggering the P140C code.

8. How can I prevent OBDII code P140C GMC from recurring?

Regular maintenance of the EGR system, including cleaning the EGR valve and passages, checking sensor functionality, and using high-quality fuel, can help prevent the recurrence of this code.

9. Are there any recalls or technical service bulletins related to OBDII code P140C GMC?

It's recommended to check with a GMC dealership or visit the manufacturer's website to see if there are any recalls or technical service bulletins related to code P140C for your specific vehicle model.

10. Can a DIY enthusiast address OBDII code P140C GMC at home?

Depending on the level of mechanical expertise, some DIY enthusiasts may be able to address the issues related to code P140C by following repair guides, using proper tools, and conducting thorough diagnostics.