P026A/000618

P026A/000618 - Charge Air Cooler: Efficiency Below Threshold - MIL ON

Possible Symptoms

• Malfunction Indicator Lamp (MIL) active
• Reduced engine output

Possible Causes

• Intercooler restricted (internal or external)
• Faulty sensor
• ECM firmware issue

Special Notes

• On some TDI CR engines, a faulty G42 / G31 sensor at the top of the intercooler may report a much higher than possible temperature:
  • IDE04938 - Sensor for temp after charge air cooler: raw value
  • Case Study - P026A/000618 - Charge Air Cooler: Efficiency Below Threshold - MIL ON

• When found in a Touareg with the 3.0L TDI CNRB engine, there may be a firmware update for this:
  • https://static.nhtsa.gov/odi/tsbs/2013/SB-10067148-5290.pdf