P011C: Charge Air Cooler Temperature/Intake Air Temperature Correlation Bank 1

What it means

The module detects that charge air cooler temperature and intake air temperature readings do not correlate within the expected limits for bank 1.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

On a turbocharged or supercharged engine with a charge-air cooler, the charge-air cooler temperature sensor measures cooled compressed air, while the intake air temperature sensor measures air at a separate point. P011C sets when the control module finds that these readings do not correlate as expected on bank 1, which can affect boost and fueling calculations.

Common causes

Most likely first.

1. Charge air cooler or intake air temperature sensor drifting or biased
2. Faulty sensor wiring or connector
3. Poor electrical connection or corrosion
4. Less commonly, a module fault

Symptoms

• Check engine light on
• Reduced engine power or boost
• Sluggish acceleration
• Changes in fuel economy

How to diagnose it

1. Review freeze-frame data and compare charge-air cooler temperature and IAT live data for bank 1 under the recorded operating conditions.
2. With the engine cold, compare both readings with ambient temperature and note which sensor appears implausible.
3. Locate the bank 1 sensors using vehicle service information and inspect their connectors and wiring for corrosion, loose contacts, heat damage, or chafing.
4. Check the charge-air cooler and intake tract on bank 1 for obvious damage, leaks, or airflow restrictions that could explain unusual temperature behavior.
5. Test the suspect sensor and its circuit against the manufacturer's specification before considering a control-module fault.

Common fixes

• Reconnect and secure a loose bank 1 temperature-sensor connector.
• Repair chafed wiring or replace a corroded connector in the affected circuit.
• Repair a damaged or leaking bank 1 charge-air cooler or intake connection found during inspection.
• Replace the biased charge-air cooler temperature sensor or IAT sensor on bank 1 if testing identifies it.

Can I keep driving?

If the engine has reduced power or boost, avoid towing, hard acceleration, and high-load driving until the cause is known. Incorrect charge-air temperature data can limit performance and affect fueling; stop if the engine runs abnormally or warning signs of overheating appear.