P0401 on Opel
Exhaust Gas Recirculation Flow Insufficient
P0401 on Opel vehicles indicates exhaust gas recirculation flow insufficient. Au7o has documented this code across 3 Opel models — most commonly on Astra, Insignia, Zafira. This code means the Exhaust Gas Recirculation (EGR) system is not flowing enough exhaust back into the engine. The EGR system recirculates a small amount of exhaust into the intake to lower combustion temperatures and reduce nitrogen oxide (NOx) emissions; the computer has determined the actual flow is below what it commanded. The most common reason is carbon buildup clogging the EGR valve or its passages. You may notice pinging/knocking, rough idle, or a check engine light, and the car will fail emissions testing. Typical repair costs on Opel range from $400 to $1,800, depending on the specific model and root cause.
Common Causes of P0401
- •Carbon buildup clogging the EGR valve or passages
- •Stuck or faulty EGR valve
- •Blocked or restricted EGR ports/tubes
- •Faulty EGR temperature or position sensor
- •Faulty DPFE/EGR pressure sensor (on applicable systems)
- •Vacuum leak or failed vacuum control (vacuum-operated EGR)
- •Wiring or connector problems at the EGR valve
P0401 on Opel by Model
Opel Astra(1 issue)
- Astra J 1.7 CDTI EGR Valve Clogging2009-2015
The A17DTR/A17DTS 1.7 CDTI diesel in Astra J (2009-2015), Mokka A, and Meriva B suffers severe EGR valve carbon buildup, typically presenting between 80,000-150,000 km. Symptoms include power loss, limp mode, and rough idle. The EGR cooler can also crack, mixing coolant with intake flow.
Opel Insignia(1 issue)
- Insignia A 2.0 CDTI EGR Cooler Crack (Coolant Loss into Intake)2008-2015
The A20DT/A20DTH 2.0 CDTI EGR cooler develops internal cracks, allowing coolant to leak into the intake. Symptoms: white smoke from exhaust, mysterious coolant loss with no external leak, sweet smell, eventual no-start as cylinders flood. Common at 100,000-180,000 km. Same engine in Astra J, Zafira C, Cascada.
Opel Zafira(1 issue)
- Zafira Tourer 1.6 CDTI EGR Cooler Failure2013-2019
The B16DTH "Whisper Diesel" 1.6 CDTI in Zafira Tourer (and shared Astra J/K) suffers EGR cooler failure with similar symptoms to the 2.0 CDTI: coolant disappearing, white smoke, and sweet smell. Typical onset 80,000-150,000 km.
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View P0401 across all makes →Frequently Asked Questions
What does P0401 mean on Opel?▼
P0401 stands for "Exhaust Gas Recirculation Flow Insufficient." This code means the Exhaust Gas Recirculation (EGR) system is not flowing enough exhaust back into the engine. The EGR system recirculates a small amount of exhaust into the intake to lower combustion temperatures and reduce nitrogen oxide (NOx) emissions; the computer has determined the actual flow is below what it commanded. The most common reason is carbon buildup clogging the EGR valve or its passages. You may notice pinging/knocking, rough idle, or a check engine light, and the car will fail emissions testing. On Opel specifically, this code is documented across 3 models.
What causes P0401 on Opel vehicles?▼
Common causes on Opel: Carbon buildup clogging the EGR valve or passages, Stuck or faulty EGR valve, Blocked or restricted EGR ports/tubes, Faulty EGR temperature or position sensor, Faulty DPFE/EGR pressure sensor (on applicable systems). Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0401 on a Opel?▼
Repair costs on Opel range from $400 to $1,800, depending on the specific model and root cause.
Which Opel models have P0401 documented?▼
Au7o has documented P0401 on 3 Opel models: Astra, Insignia, Zafira.