Exploring Automotive Electrical Faults

Bad Coolant Temperature Sensor? Symptoms And Tips To Replace It

Taking care of simple problems, like replacing the coolant temperature sensor in your car, can save you some money on car repairs. The following guide will help you diagnose a bad coolant temperature sensor and help you replace it if necessary.

Symptoms Of A Bad Coolant Temperature Sensor

One of the primary functions of your coolant temperature sensor is to tell you if the engine is overheating. But this sensor is also involved in proper air-to-fuel mixture. Your engine's computer uses this sensor to find out if the engine is too cold to function properly. The computer will make a richer air-to-fuel mixture when the engine is cold because it needs more power at this time. Your vehicle needs a delicate balance to function properly, and this sensor can throw that balance off if it is faulty.

The following are some signs of a bad coolant temperature sensor:

  • You might get poor gas mileage because your engine will have a hard time knowing how much fuel to use
  • There may be black smoke coming out of your exhaust pipe
  • You may have trouble starting your car at hot operating temperatures
  • Your car may not pass an emissions test
  • Frequent inexplicable overheating incidents
  • You might see your check engine light come on

You can talk to your auto care specialist about the aforementioned symptoms. He or she can help you detect and confirm the issue.

How To Replace Your Coolant Temperature Sensor

You will need the following:

  • Safety goggles and gloves
  • Your socket wrench set
  • New coolant
  • Drip pan
  • Teflon tape
  • A new temperature sensor that is specific to your vehicle
  • Your owner's manual
  • Jack
  • Torque wrench

To change your coolant temperature sensor, follow the steps below:

  1. Park your vehicle on level ground. Be sure to let it cool down completely.
  2. Unplug your battery as a precaution.
  3. Jack up your vehicle, and place a drip pan under your vehicle. Unscrew the pet cock that holds the coolant in your radiator. Let 1 gallon of coolant drain from your vehicle, and close it.
  4. Let your car down, and look for the coolant temperature sensor. Use your owner's manual to find the sensor. But most likely you will find it under the fan shroud, which is why it is wise to remove this shroud using your tools.
  5. The sensor will have a terminal exposed with a wire connected to it.
  6. Unlodge this wire from the sensor as carefully as you can.
  7. Use your socket wrench to carefully unscrew the sensor in a counterclockwise direction.
  8. Clean off the area as much as possible, and apply teflon tape to your new sensor.
  9. Tighten the sensor with your fingers.
  10. Use your manual to find out the torque your sensor needs, and set your torque wrench to that specification. Continue to tighten your sensor carefully as tight as it requires.
  11. Reconnect your wire, and put back the fan shroud back if you removed it.
  12. Add coolant to your radiator, and you are done.

That is how simple it is to take care of this issue. Remember that you can talk to your auto care specialist if you feel uncomfortable about any of the aforementioned steps. Contact a company like Slipstream Autocare for more information.