IAT Sensor Circuit Intermittent High Voltage
1995-2005 Pontiac Sunfire 2.2L I4
Description
The PCM detected intermittent high voltage on the Intake Air Temperature sensor circuit, indicating a sporadic open circuit or connection issue.
Symptoms
- Check Engine Light (intermittent)
- Incorrect fueling in cold weather
- Poor fuel economy
- Intermittent performance issues
Common Causes
- Loose IAT sensor connector
- Intermittent open in wiring
- Faulty IAT sensor
- Corroded terminals
Diagnostic Steps
- Wiggle test IAT connector while monitoring signal
- Inspect wiring for damage
- Test IAT sensor resistance
- Check connector terminals
Repair Notes
Clean and secure IAT sensor connector. Replace sensor if resistance is out of spec.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1111 on Other Vehicles
Pontiac Aztek
2001-2005 3.4L V6
Pontiac Bonneville
1990-1999 3.8L V6
Pontiac Bonneville
2000-2005 3.8L V6
Pontiac Bonneville GXP
2000-2005 4.6L V8
Pontiac Bonneville GXP
2000-2005 4.6L V8 Northstar
Pontiac Bonneville SSEi
1992-1999 3.8L Supercharged V6
Pontiac Bonneville SSEi
1992-1999 3.8L V6 Supercharged
Pontiac Firebird
1993-1997 3.4L V6
Common Questions
What does code P1111 mean on a 1995-2005 Pontiac Sunfire?
P1111 stands for "IAT Sensor Circuit Intermittent High Voltage". The PCM detected intermittent high voltage on the Intake Air Temperature sensor circuit, indicating a sporadic open circuit or connection issue.
What are the symptoms of P1111 on a Pontiac Sunfire?
Common symptoms of P1111 include: Check Engine Light (intermittent), Incorrect fueling in cold weather, Poor fuel economy, Intermittent performance issues.
What causes P1111 on a 1995-2005 Pontiac Sunfire?
Common causes of P1111 include: Loose IAT sensor connector, Intermittent open in wiring, Faulty IAT sensor, Corroded terminals.