What it means
The control module detects a low signal in the EGR sensor E circuit. The sensor’s function and the resulting EGR response depend on the vehicle.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
EGR sensor E provides feedback about part of the exhaust gas recirculation system, although its precise role depends on the vehicle. P2387 sets when the control module detects the sensor E signal below its expected electrical range, often because the signal is grounded or the circuit has excessive resistance.
Common causes
Most likely first.
- Signal line shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
How to diagnose it
- Save freeze-frame data and check sensor E live data for a reading that stays unusually low.
- Locate sensor E using vehicle service information and inspect its connector and harness for chafing, moisture, corrosion, or damaged insulation.
- Use the wiring diagram to check whether the signal wire is shorted to ground.
- Check connector contact and measure signal, supply, and ground circuits against the manufacturer’s specification.
- If wiring and connections are sound, test sensor E and its EGR-related response using the manufacturer’s procedure.
Common fixes
- Repair a signal wire shorted to ground or chafed through its insulation.
- Clean, dry, and secure corroded or contaminated connector terminals.
- Repair damaged wiring or connector seals that allow moisture in.
- Replace sensor E if it fails the manufacturer’s test.
Can I keep driving?
Drive gently only if the engine is running smoothly, and avoid heavy loads if knocking, hesitation, or power loss occurs. Faulty EGR feedback can increase NOx emissions, and worsening roughness or power loss is a reason to stop driving.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.