The 2019 GMC Sierra's P0114 code indicates the ECU detected intermittent or erratic signals from the IAT sensor. Unlike consistent high or low codes, intermittent codes suggest a connection that comes and goes—typically pointing to loose connections or damaged wiring.
What P0114 Means
P0114 indicates the IAT signal is dropping out, spiking, or behaving erratically. The sensor may work correctly most of the time but periodically send incorrect data. This intermittent pattern typically points to connection issues rather than sensor failure.
Sierra Engine and IAT Location
The 2019 Sierra offers the 5.3L V8, 6.2L V8, or 4.3L V6. On GM trucks, the IAT sensor is often integrated into the MAF sensor assembly. This means IAT issues may be related to the MAF connector or shared wiring.
Common Causes of Intermittent IAT Signals
Loose or corroded connections cause most intermittent issues. The MAF/IAT connector on GM trucks can develop contact problems from engine vibration and environmental exposure. The connector may look secure but have worn internal terminals.
Damaged wiring that maintains contact most of the time but breaks under certain conditions causes intermittent signals. Wires can have internal breaks that open under heat or vibration.
A sensor with failing internal components may work intermittently. Temperature cycling causes borderline solder joints or connections to make or break contact.
Diagnostic Strategy
Connect a scan tool and monitor IAT data while wiggling the MAF/IAT connector and associated wiring. Look for changes in readings correlating with manipulation. Drive while monitoring—note any correlation between symptoms and data anomalies. Inspect the connector terminals for wear, corrosion, or damage.