P04E9
EGR Temperature Sensor D Circuit Intermittent or Erratic
Same as P04D2 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.
Same as P04D2 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.
Common causes
- high
Intermittent contact at connector
One of the most commonly reported causes for this code — check this first.
Typical part cost: $130-440
- low
Connector with intermittent contact under vibration
Less common, but worth ruling out after the more likely causes.
Typical part cost: $130-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P04E9 mean?
P04E9 means "EGR Temperature Sensor D Circuit Intermittent or Erratic". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04E9?
intermittent contact at connector; connector with intermittent contact under vibration; harness routed against vibrating component — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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