⚡ AUTO CODE FIX
🔍
EmissionsModerate✅ DIY Friendly

P0401

Exhaust Gas Recirculation Insufficient Flow

Not enough EGR flow during operating conditions.

SeverityModerate
CategoryEmissions
Est. Repair Cost$50–$400
Code TypePowertrain
DIY RepairYes

⚡ Common Causes

⚠️ Symptoms

✅ How to Fix — Step by Step

  • Step 1:Clean EGR valve thoroughly
  • Step 2:Clean EGR passages
  • Step 3:Replace DPFE sensor (Ford specific)
  • Step 4:Check vacuum supply to EGR
  • Step 5:Replace EGR valve
💡 Pro Tip: On Ford vehicles the DPFE sensor is a very common cause of P0401 — a cheap fix.

Repair Cost Estimate

Full Repair Estimate
$50–$400
DIY Possible?
YES
Severity
Moderate

Frequently Asked Questions

What does OBD2 code P0401 mean?+
P0401 stands for Exhaust Gas Recirculation Insufficient Flow. Not enough EGR flow during operating conditions.
What causes code P0401?+
Clogged EGR valve; Blocked EGR passages with carbon; Faulty DPFE sensor; Broken EGR vacuum hose
How do I fix code P0401?+
Clean EGR valve thoroughly; Clean EGR passages; Replace DPFE sensor (Ford specific); Check vacuum supply to EGR; Replace EGR valve
How much does it cost to fix P0401?+
Estimated repair cost for P0401 is $50–$400.
Is P0401 DIY-friendly?+
Yes — P0401 is generally DIY-friendly with basic tools.

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