All codes › P0401
P0401: Exhaust Gas Recirculation "A" Flow Insufficient Detected
What it means
Not enough exhaust gas is flowing back through the EGR system.
Severity: Medium Low EGR flow can cause pinging and higher NOx emissions.
Common causes
- Carbon-clogged EGR passages (most common)
- Stuck-closed EGR valve
- Failed DPFE/EGR sensor
- Vacuum leak to EGR valve
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Sometimes DIY. Cleaning carbon from the EGR valve and passages often fixes it.
Repair cost
SEEDED ESTIMATE Roughly $260–$560
Most likely repair: egr valve. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| EGR valve | $164 | $164 | Typical listed retail range, source (single example listing ($163.99)) |
| Labor 1–2.5 hr | $100 | $400 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0401 are verified.
Verified reader invoices for P0401: 0. Share your repair bill to help build real costs.
Tools that can read P0401
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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