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DTC codes / P00xx · Fuel and air metering and auxiliary emission controls / P00E2

P00E2Charge Air Cooler Coolant Temperature Sensor A Intermittent/Erratic

P00E2 indicates that the powertrain control module (PCM) has detected an intermittent or erratic signal from the charge air cooler (CAC) coolant temperature sensor A. This sensor monitors the temperature of the coolant that circulates through the air-to-liquid charge air cooler, and the PCM uses that data to protect the engine from overheating and to optimize combustion; an erratic signal means the voltage from the sensor is jumping around or dropping out unpredictably rather than reporting a steady temperature.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaFuel and air metering and auxiliary emission controls

Symptoms you may notice

  • Illumination of the check engine light, often with no other noticeable symptoms.
  • Reduced engine power or limp mode under heavy load or during sustained acceleration.
  • Poor fuel economy or slightly rough running when the engine is under boost.
  • Inconsistent or fluctuating temperature readings on a scan tool data stream for the CAC coolant sensor.
  • In rare cases, the engine cooling fan may run constantly or not at all due to conflicting temperature data.

Common causes, most likely first

  1. A faulty charge air cooler coolant temperature sensor with an internal intermittent connection or failing thermistor.
  2. Damaged, chafed, or corroded wiring in the sensor circuit, especially near hot or vibrating components.
  3. Loose or contaminated electrical connector pins at the sensor or PCM, causing an erratic connection.
  4. Coolant contamination or low coolant level in the charge air cooler circuit, leading to unstable sensor readings.
  5. A failing PCM driver circuit for the sensor reference or signal return, though this is less common.
  6. Aftermarket or incorrect sensor installed previously that does not meet the OEM signal specification.

How to diagnose and fix it

  1. Use a scan tool to verify the fault is current and record the freeze-frame data, then clear the code and test-drive to see if it returns.
  2. Visually inspect the sensor, its connector, and the wiring harness for damage, corrosion, or loose pins, repairing as needed.
  3. Check the coolant level and condition in the charge air cooler circuit, topping off or flushing if contaminated.
  4. Back-probe the sensor connector and monitor the signal voltage with a multimeter while wiggling the harness to detect intermittent opens or shorts.
  5. Compare the sensor's live data reading against a known-good value or a non-contact infrared thermometer at the sensor location to confirm accuracy.
  6. Replace the charge air cooler coolant temperature sensor if resistance tests or live data confirm it is erratic.
  7. After repair, clear the codes and perform a road test under load to confirm the signal remains stable and the code does not reset.

What a wiggle test reveals about P00E2

  • An intermittent sensor code often sets because of a poor connection inside the sensor itself, not because the sensor has failed completely, so a resistance test while heating and vibrating the sensor can expose the fault.
  • The charge air cooler coolant temperature sensor shares its reference voltage and ground with other sensors on many engines, so a short in a neighboring circuit can corrupt this signal and set P00E2 without any fault in the sensor itself.
  • Technicians sometimes replace the sensor only to find the code returns because the connector terminal tension was lost, so always check that the female terminals grip the male pins firmly.
  • This code can be set by air pockets in the charge air cooler coolant circuit after a coolant service, which cause the sensor to see rapid temperature swings that the PCM interprets as erratic.

Can I keep driving with P00E2?

You can usually continue driving with P00E2 because the fault is intermittent and the engine remains protected by other sensors, but avoid sustained heavy acceleration or towing until it is repaired, as an erratic reading may cause the PCM to reduce power unexpectedly.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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