OBD-II code · Powertrain (generic)
P04E8 EGR Temperature Sensor D Circuit High
Same as P04D1 on EGR temperature sensor D. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.
Is it safe to drive with P04E8?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySignal shorted to supply
- Less likelyConnector pins corroded - high contact resistance
- Less likelySupply wire pinched against B+ source
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
- Often, with basic tools
- Typical labour
- 0.6–1.6 h
- Emissions test
- Likely to fail
- Parts involved
- Egr Temperature Sensor D
Related codes
- P040DEGR Temperature Sensor A Circuit High
- P041DEGR Temperature Sensor B Circuit High
- P04D1EGR Temperature Sensor C Circuit High
- P04E5EGR Temperature Sensor D Circuit
- P04E6EGR Temperature Sensor D Circuit Range or Performance
- P04E7EGR Temperature Sensor D Circuit Low
- P04E9EGR Temperature Sensor D Circuit Intermittent or Erratic
- P04EAEVAP System Small Leak Detected Fuel Tank Side
- P04EBEVAP System Small Leak Detected Fresh Air Side
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.