P0400
Moderate
Powertrain
Exhaust Gas Recirculation Flow Malfunction
Common Causes
Clogged EGR valve or passages
Failed EGR valve
Damaged EGR vacuum lines
Failed DPFE sensor (Ford)
Common Symptoms
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Quick Info
| Code | P0400 |
| System | Powertrain |
| Severity | Moderate |
Disclaimer
This information is for diagnostic guidance only. Always verify repairs with a qualified technician before performing safety-critical work.
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