P0402
EGR Flow Excessive Detected
2019-2019 Buick Enclave 3.6L V6
Moderate SeverityPowertrainGeneric (SAE)
The 2019 Buick Enclave is equipped with a 3.6L V6 engine. Below you'll find detailed p0402 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
The EGR system is flowing too much exhaust gas.
Symptoms
- Check Engine Light
- Rough idle
- Stalling
- Surging
- Poor acceleration
Common Causes
- EGR valve stuck open
- Faulty EGR solenoid
- Vacuum leak to EGR valve
- Faulty DPFE sensor reading low
Diagnostic Steps
- Check EGR valve for stuck-open condition
- Test EGR solenoid
- Check vacuum lines
- Test DPFE/position sensor
Repair Notes
Replace EGR valve if stuck open. Repair vacuum lines.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0402 on Other Vehicles
Common Questions
What does code P0402 mean on a 2019-2019 Buick Enclave?
P0402 stands for "EGR Flow Excessive Detected". The EGR system is flowing too much exhaust gas.
What are the symptoms of P0402 on a Buick Enclave?
Common symptoms of P0402 include: Check Engine Light, Rough idle, Stalling, Surging, Poor acceleration.
What causes P0402 on a 2019-2019 Buick Enclave?
Common causes of P0402 include: EGR valve stuck open, Faulty EGR solenoid, Vacuum leak to EGR valve, Faulty DPFE sensor reading low.
Last updated: March 2026