P1119: Manifold Air Temp Sensor Out of Range High
The P1119 code indicates that the Engine Control Module (ECM) has detected a signal from the Manifold Air Temperature (MAT) sensor that is above the expected voltage range, typically corresponding to an air temperature reading below -40°F or above 250°F. This sensor measures the temperature of the air entering the intake manifold, and the ECM uses this data to adjust fuel delivery and ignition timing. An out-of-range high signal suggests a short to voltage, open circuit, or a faulty sensor. This can lead to incorrect air-fuel mixture, causing performance issues and increased emissions.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Poor engine performance (hesitation, rough idle)
- Decreased fuel economy
- Hard starting in cold weather
- Black smoke from exhaust (rich mixture)
2. Most Common Causes
- Faulty Manifold Air Temperature (MAT) sensor
- Short to voltage in the sensor circuit
- Open circuit or damaged wiring/connector
- Corroded or loose electrical connections
- ECM malfunction (rare)
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Visually inspect the MAT sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor's resistance with a multimeter; compare to manufacturer specifications (typically 2-10 kΩ at room temperature).
Step 4: Check for voltage at the sensor connector (should be 5V reference from ECM). If voltage is high, suspect a short to power.
Step 5: If sensor and wiring are okay, replace the MAT sensor and clear the code.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code, as it can cause poor fuel economy, drivability issues, and potential damage to the catalytic converter due to incorrect air-fuel mixture.
How much does it cost to fix?▼
The cost to fix P1119 typically ranges from $50 to $150, including parts (MAT sensor $20-$50) and labor (0.5-1 hour at $80-$100 per hour).
5. Commonly Affected Makes
This is a manufacturer-specific code. The exact manufacturer is not confirmed in our current database.