What does it mean?
P1119 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Manifold Air Temperature Sensor High Input .
Symptoms
- Check engine light on with the intake air temperature stuck at an implausibly cold value
- Rich mixture with black smoke and a strong fuel smell
- Rough idle and hesitation, especially when the engine is already warm
- Higher fuel consumption and sooty spark plugs over time
- Hard hot starting, since the module fuels for cold air
- Reduced power and duller throttle response
Likely causes
- Broken or disconnected signal wire between the sensor and the module
- Open sensor ground wire or a corroded ground point on the engine
- Sensor element open internally after long exposure to intake heat
- Terminal backed out of the connector or a broken connector latch
- Corrosion inside the connector raising the contact resistance
- Signal wire shorted to the 5 V reference through a chafed section of loom
- Module input fault as the last possibility
How to fix it
- Read the live intake air temperature; a value far colder than ambient with a warm engine confirms the high input
- Unplug the sensor and briefly bridge the connector pins with the ignition on — the reading should jump to maximum if the wiring and module are good
- If nothing changes, test the signal and ground wires for continuity back to the module
- Measure the sensor resistance and compare it with the temperature table; an open reading condemns the sensor
- Inspect the connector for corrosion, pushed-back terminals and heat damage from the manifold
- Check the loom for chafing where it could touch a reference or supply wire
- Repair the wiring or replace the sensor, then confirm the reading matches ambient temperature on a cold engine