OBD-II code · Powertrain (generic)
P04DE Cold Start EGR A Flow Excessive Detected
Same as P04DD with EGR flow above the cold-start target - typically valve sticking open during the cold phase or position sensor offset low.
Is it safe to drive with P04DE?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyEGR valve A sticking open when cold
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1.5–4 h
- Emissions test
- Likely to fail
- Parts involved
- Egr Valve A, Egr Position Sensor A
Related codes
- P2AA4Cold Start EGR B Flow Excessive Detected
- P04DBCrankcase Ventilation System Disconnected
- P04DCFuel Fill Door Position Sensor Circuit Range or Performance
- P04DDCold Start EGR A Flow Insufficient Detected
- P04DFEVAP System Purge Control Valve A Performance Stuck Open
- P04E0EVAP System Purge Control Valve A Stuck Closed
- P04E1Crankcase Ventilation Hose Connection Sensor Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.