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Bad Coolant Temperature Sensor Symptoms Check Engine Light. Poor Mileage. Electrical Cooling Fans not coming on. Black Smoke from the Exhaust Pipe. Difficult Starting Condition. Engine Overheats. Poor Idling. Poor Engine performance.
What can a bad temperature sensor cause?
If the coolant temperature sensor malfunctions, it could cause your car engine to get overheated. While sometimes a faulty sensor sends a permanent cold signal to the engine, it can also send a permanent hot signal. When this happens, the car might misfire, or it could lead to engine knocking.
How do I know if my temperature sensor is working?
Gently lower the end of the sensor into the water until the entire device is fully submerged. Wait a minute or so for the screen to give you a reading of the cold water. Once you have a reading, write down the measurement for reference. A common reading for a temperature sensor in cold water is around 5 volts.
What does a engine coolant temperature sensor do?
A coolant temperature sensor (CTS) (also known as an ECT sensor or ECTS (engine coolant temperature sensor) is used to measure the temperature of the coolant/antifreeze mix in the cooling system, giving an indication of how much heat the engine is giving off.
What happens if I unplug coolant temperature sensor?
What Happens If You Unplug The Coolant Temp Sensor? Unplugging the engine coolant sensor while the car is running will likely cause the engine to stumble and run rough. The engine light may not come on imminently, but a DTC (Diagnostic Trouble Code) will be logged in the PCM.
Will a bad temperature sensor cause a misfire?
Engine Overheating The coolant temperature sensor can also fail in a manner; that causes it to send a permanently hot signal. All of which can result in overheating, and even misfires or engine ping.
Can a temp sensor affect engine starting?
If the sensor is reading too high of temperature when compared to the ambient air temperature sensor when first started then the computer would see it as a problem and turn on the check engine light to use a known good reading. No start will not be caused by the sensor.
Does the coolant temp sensor control the fan?
The sensor works by measuring the temperature that’s being given off by the thermostat and/or the coolant itself. The temperature is then sent to the on-board control system. As the control system receives the temperature from the CTS, it may trigger the cooling fan to either shut off or turn on.
How do you test a sensor?
Use this procedure to test the sensor. Remove the sensor and check it for bad connections or exposed wires. Re-install the sensor and turn on the engine. Set the digital volt ohm meter to read millivolts. Switch the engine on again and observe the meter reading.
What is the resistance of a coolant temperature sensor?
Working principle of the ECT sensor In cold engine and an ambient temperature of 20 ºC the sensor resistance is between 2000Ω and 3000Ω. After the engine start, coolant temperature begins to rise. ECT gradually heats and its resistance reduces proportionately. At 90 ºC its resistance is in the range of 200Ω to 300Ω.
What are three ways that temperature sensors can be tested?
Physically inspect sensor for damage. Check temperature transmitter. Test faulty thermocouple with a multimeter. Test faulty resistance thermometer with a multimeter.
What are the symptoms of a faulty cooling fan switch?
Common signs include engine overheating, the Check Engine Light coming on, and a broken or shorter signal wire.
Can a car run without a coolant temperature sensor?
If you unplug the sensor when the engine is cold the engine may run smoothly at first but as the engine warms up the a/f mix will become too rich and the engine will start misfiring and possibly stall.
Can a bad temp sensor cause stalling?
The signal from the coolant temperature sensor tells the engine’s computer when to apply extra gasoline during a cold start. A faulty sensor can confuse the computer, keeping it from providing enough fuel. As a result, the engine may hesitate or stall.
How often do coolant temp sensors go bad?
At 100,000 miles, the engine coolant temperature sensor needs to be replaced. The engine cooling system’s sensor could fail much earlier if you don’t maintain it.
Can a bad coolant temp sensor cause high idle?
Yes it could. But there is a easy way to check before replacing parts, use a live data OBDII scanner to watch the engine temp, that will show you what the ECU is reading. Just because the gauge reads normal does not mean the ECU reads the correct temp.
Can a bad thermostat cause starting problems?
Though a hot engine is one of the signs that something may be wrong, your engine could also start running cold. A cold engine is also caused by a bad thermostat and can affect the operation of your car.
What sensors can cause a car not to start?
A bad Crankshaft Position sensor is a common cause of no starts. The signal from this sensor goes to the PCM or ignition module that switches the ignition coil(s) on and off. If you have an RPM signal, a bad ignition module or PCM may not be switching the coil(s) on and off.
What sensors can stop a car from starting?
A crankshaft position sensor (crank sensor) is an important device measuring the engine RPM and tracing the crankshaft position. The car won’t start if the crankshaft position sensor doesn’t work properly. The crank sensor can fail, or its wiring can get damaged. This may cause the car to stall or not start.
