P0402 Chevrolet Code - Exhaust Gas Recirculation Flow Excessive
Quick Answer
The P0402 code for Chevrolet vehicles indicates that there is an excessive flow of exhaust gas recirculation (EGR) in the system. Common causes include Faulty EGR valve, Clogged EGR system passages, Malfunctioning EGR sensor. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0402 Chevrolet indicates Exhaust Gas Recirculation Flow Excessive.
- Common causes
- Common causes include Faulty EGR valve, Clogged EGR system passages, Malfunctioning EGR sensor.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0402 Chevrolet Description
The P0402 code for Chevrolet vehicles indicates that there is an excessive flow of exhaust gas recirculation (EGR) in the system. The EGR system is responsible for recirculating a portion of the engine's exhaust gases back into the intake manifold to reduce emissions and control combustion temperatures. An excessive flow of EGR can lead to a decrease in engine performance, increased fuel consumption, and higher emissions levels. This issue can be caused by a malfunction in the EGR valve, a blockage in the EGR system, or a problem with the EGR sensor.
Common Causes of P0402 Chevrolet
- Faulty EGR valve
- Clogged EGR system passages
- Malfunctioning EGR sensor
- Vacuum leaks in the EGR system
- Carbon buildup in the EGR system
Symptoms of P0402 Chevrolet
- Check engine light illuminated
- Rough idling or stalling
- Decreased fuel efficiency
- Engine knocking or pinging sounds
- Increased emissions levels
How to Fix P0402 Chevrolet
- Inspect and clean EGR valve and passages
- Test EGR sensor for proper operation
- Replace faulty EGR valve or sensor
- Clear diagnostic trouble codes and reset the ECU
- Perform a test drive to ensure the issue has been resolved
Cost to Fix P0402 Chevrolet
The typical repair costs for addressing a P0402 code in a Chevrolet vehicle can range from $200 to $500, depending on the specific cause of the issue and the cost of parts and labor in your area. It's important to consult with a professional mechanic to accurately diagnose the problem and provide an estimate for the repair. Remember that labor rates and parts prices can vary, so it's advisable to get multiple quotes before proceeding with the repair.
Need more information about the P0402 Chevrolet code?
Need more information on how to fix the P0402 Chevrolet code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0402 Chevrolet code diagnosed by a professional: Find a repair shop in your area
Information for Specific Chevrolet Models
- P0402 2014 Chevrolet Silverado — Exhaust Gas Recirculation Flow Excessive
- P0402 2015 Chevrolet Silverado — Exhaust Gas Recirculation Flow Excessive
- P0402 2016 Chevrolet Silverado — Exhaust Gas Recirculation Flow Excessive
- P0402 2017 Chevrolet Silverado — Exhaust Gas Recirculation Flow Excessive
- P0402 2018 Chevrolet Silverado — Exhaust Gas Recirculation Flow Excessive
Frequently Asked Questions about P0402 Chevrolet Code
What does the OBDII code P0402 mean on a Chevrolet?
Code P0402 indicates that the Exhaust Gas Recirculation (EGR) system is allowing too much exhaust flow back into the intake manifold, exceeding the manufacturer's specifications.
What are the common symptoms of code P0402 in a Chevrolet?
Common symptoms include the check engine light turning on, rough idling, reduced engine performance, poor fuel economy, and increased exhaust emissions.
What causes the P0402 code to appear on a Chevrolet?
Common causes include a stuck-open EGR valve, carbon buildup in the EGR passages, a faulty EGR sensor, or issues with the engine control module (ECM).
Can a faulty EGR valve trigger the P0402 code?
Yes, a stuck-open or malfunctioning EGR valve is one of the primary causes of the P0402 code.
How can I fix the P0402 code on my Chevrolet?
Repairs may involve cleaning or replacing the EGR valve, clearing carbon buildup in the EGR passages, replacing a faulty EGR sensor, or addressing wiring issues.
Is it safe to drive my Chevrolet with the P0402 code?
Driving with the P0402 code is not recommended, as it can lead to poor performance, higher emissions, and potential engine damage if left unaddressed.
How much does it cost to fix the P0402 code on a Chevrolet?
Repair costs vary, but replacing an EGR valve typically costs between $150 and $400, including parts and labor. Cleaning the EGR system is less expensive.
Can a vacuum leak cause the P0402 code?
A vacuum leak is not a direct cause of P0402, but it can contribute to irregular EGR system operation, which may trigger the code.
How do I diagnose the P0402 code on my Chevrolet?
Diagnosis involves scanning for trouble codes, inspecting the EGR valve for sticking or damage, checking for carbon buildup, and testing the EGR sensor and related wiring.
Can a clogged catalytic converter cause the P0402 code?
While uncommon, a clogged catalytic converter can sometimes cause backpressure issues that may affect EGR system performance, potentially triggering the P0402 code.
Discuss the causes and fixes for P0402 Chevrolet OBDII Code
Code P0402 Chevrolet comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.