P0119 Code: Engine Coolant Temperature Sensor Circuit Intermittent
🟠 Moderate severity · drivable
You can usually drive, but the engine may start hard or run rough when the coolant signal drops out.
What P0119 means
The engine coolant temperature sensor signal is jumping around or dropping out. The computer sees coolant temperature readings that change suddenly or go missing. This can cause hard starting, rough idle, and poor fuel economy.
Symptoms
- Check engine light on
- Hard starting
- Rough idle
- Poor fuel economy
- Temperature gauge behaves oddly
Common causes
- most common: Corroded or loose connector
- common: Damaged wiring
- common: Faulty ECT sensor
- less common: Low coolant or air in the system
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Clean and reseat the connector | Yes | $0–20 |
| Repair damaged wiring | Yes | $20–80 |
| Replace the ECT sensor | Yes | $20–80 |
| Check coolant level and bleed air | Yes | $10–40 |
Frequently asked questions
Can I drive with P0119?
Yes, but the engine may start hard or run rough when the signal drops. Check the connector first.
What makes the reading erratic?
Loose connections, damaged wires, and failing sensors cause readings that jump around.
Do I need to bleed the cooling system?
If coolant is low or air is trapped near the sensor, the reading can be unstable. Top up and bleed if needed.
Related codes
P0115
P0115 Code: Engine Coolant Temperature Circuit Malfunction
P0116P0116 Code: Engine Coolant Temperature Sensor Range/Performance
P0117P0117 Code: Engine Coolant Temperature Circuit Low Input
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.