OBD2 Error Code P0118: How to Fix It

Q: Can I drive with P0118 error code?

You can drive short distances, but avoid extended driving. The engine may run poorly, have reduced fuel economy, and could potentially overheat if the actual temperature isn't being read correctly.

Q: How much does it cost to fix P0118?

DIY repairs typically cost $20-50 for a new sensor. Professional diagnosis and repair can range from $100-300 depending on whether it's just the sensor or if wiring repairs are needed.

Q: What causes ECT sensor to fail?

Common causes include normal wear over time, contaminated coolant, overheating episodes, electrical shorts, corrosion from moisture, and physical damage from vibration or impact.

Q: Will P0118 cause my car to overheat?

P0118 itself won't cause overheating, but it may prevent your car's computer from properly managing cooling fans and fuel mixture, which could lead to overheating if not addressed.

Q: How do I know if it's the sensor or the wiring?

Test the sensor resistance with a multimeter - if it reads within spec when cold and changes smoothly with temperature, the issue is likely wiring. If the sensor shows no resistance or erratic readings, replace the sensor.

Abstract

OBD2 error code P0118 indicates your engine coolant temperature sensor is sending a voltage signal that's higher than expected to your car's computer. This usually means the sensor itself has failed, there's a wiring problem, or the coolant temperature is genuinely too hot.