Temperature gauge reads a little lower on highway
When I'm in stop and go traffic my temp gauge sits on the middle but when I am on an open road or highway my gauge goes down from half to a quarter. I've owned more than one Grand Marquis before and it never did this. There is also no check engine light. Is this just a bad thermostat or normal operation?
My car has 131000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hi There,
It sounds like you may have a faulty thermostat. The thermostat regulates the flow of the coolant in your car’s engine and controls when the coolant flows in and out of the motor from the radiator by opening and closing at specific temperatures. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature.
It sounds like you may have a faulty thermostat. The thermostat regulates the flow of the coolant in your car’s engine and controls when the coolant flows in and out of the motor from the radiator by opening and closing at specific temperatures. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature.
How to Identify and Fix Common car Problems ?
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The reason the temperature gauge drops when driving is because there`s much greater airflow through the radiator when you`re at speed than at idle. That increased airflow drops the temperature on the coolant coming into the engine.
In most cars, the temperature needle will be at or near the center when the engine is at normal operating temperature, which usually takes at least a minute or two to reach after starting a cold engine.
Notes: 195 °F (91 °C), Engine Coolant Thermostat.
Your car actually has a thermistor – not a thermometer. Car thermistors are a poor representation of the actual outside temperature. This is because the thermistor is exposed to re-radiated heat from the road surface.
Examples include an underactive thyroid (hypothyroidism), poor nutrition or anorexia nervosa, diabetes, stroke, severe arthritis, Parkinson`s disease, trauma, and spinal cord injuries. Medications. Some drugs can change the body`s ability to regulate its temperature.
Look online for the hot and cold readings of your vehicle`s temperature sensor — or check the car`s manual — and compare your readings to see if they closely match. If they do, your sensor is functioning properly and you may have an issue elsewhere. If not, you`ll need to replace your sensor.
The Thermocouple As A Temperature Sensor. The Thermocouple is by far the most commonly used type of all the temperature sensor types. Thermocouples are popular due to its simplicity, ease of use and their speed of response to changes in temperature, due mainly to their small size.
A 180-degree thermostat is better for engine efficiency—aka better fuel mileage and decreased emissions. A 160-degree thermostat is designed to maintain a lower engine operating temperature, which tends to make a little bit more horsepower and torque.
How Low is Too Low to Set My Thermostat? If you`re going to be leaving your home or traveling for the winter, it`s best to keep your thermostat set no lower than 55 degrees. If you don`t, you could risk having your pipes freeze over.
To do so, locate your home`s thermostat and tape an accurate thermometer on the wall next to it. Wait 15 minutes and check the temperature reading on both devices. If your readings are three or fewer degrees apart, you should be good to go.
It`s important to be consistent because your temperature fluctuates hour by hour. The average body temperature is 98.6 degrees Fahrenheit but varies from 97.7 to 99.5 degrees. Fluctuations are due to changes in hormonal activity over the course of the day, your environment, and physical activity.
The most common cause of faulty temperature readings is a broken coolant temperature sensor (CTS). The part, which is normally located near a vehicle`s thermostat near the base of the radiator (consult your owner`s manual or repair guide) can get gunked up and fail.
If you notice that the actual temperature of your room is at least five degrees warmer than your desired temperature and your air conditioning system doesn`t kick on, you could have a bad thermostat. If you`re still using a manual version, use this time to upgrade to a smart model.
People may feel hot for many reasons other than a fever. Some causes may be temporary and easy to identify, such as eating spicy foods, being in a humid environment, or experiencing stress and anxiety. However, some people may feel hot frequently for no apparent reason.
Hypothermia is a dangerous drop in body temperature below 35C (95F). Normal body temperature is around 37C (98.6F). Hypothermia can be serious if not treated quickly.
You simply set the gauge`s temperature probe in a pot filled with water on your stove, then set the gauge and the rest of the capillary tube away from the heat. Turn on the heat and your gauge`s needle should move as the water temp. begins to rise. When the needle hits about 212 degrees F, the water should be boiling.
Your radiator fan should kick in at about 200 degrees Fahrenheit. If you notice your vehicle is overheating or at the very least running hotter than it normally does, listen for the fan to see if you can hear it.
Normal coolant temperature will be around 195 to 220 Fahrenheit (approx 90°C) and anything above or below this can start causing problems.
On most modern cars, the cooling fan is controlled by the Engine Control Unit (ECU) which gets a signal from the coolant temperature sensor. If it`s not working, the fan won`t turn on when it needs to, which means the engine might overheat.
If you notice that your engine overheats, the coolant temperature sensor could be the problem. At times, the coolant temperature switch may fail such that it starts transmitting hot signals permanently. This causes the computer to erroneously counterbalance the signal, thereby causing the engine to misfire or overheat.
There are two temperature sensors in some vehicles, one to send information from the engine system to the control unit and another from the control unit to the dashboard. The device follows the principle of dependence of potential difference in temperature.
A low-temp thermostat gives the cooling system a head start. This will help to prevent Engine Detonation and overheating.
If you don`t mind the bills and ecological impact, you have the encouragement of the World Health Organisation to keep the house warm. They recommend an indoor temperature of at least 18 degrees, declaring that you face health risks at lower temperatures.
One of the most common reasons that your thermostat is incorrectly reading your home`s temperature is that the temperature sensor is malfunctioning or has failed completely. Replacing a temperature sensor can be very difficult, so there are a few things you should try before you schedule a replacement.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
I have a problem with the temperature gauge – 2002 Buick Rendezvous
ANSWER : Hello. The temperature gauge is going to elevate based on the resistance of the sensor. The first thing to check is the temperature sending unit. The wires or the sensor itself may be corroded or damaged. This would cause extra resistance in the system and cause the gauge to be off.
You can test the readings coming from the temperature sensor. You will want to test for resistance and match it to the correlated temperature. You can find these specifications based on make and model. This would inform you of what the gauge thinks the temperature is versus what the scanner is reading. If they are off, then you know the sensor is bad and you should replace it. The sensor will signal the computer as to when the fans should be turning on. If the fans are not turning on soon enough, this would be the cause.
I recommend having a certified mechanic, such as one from YourMechanic, come to your location to determine if the gauge is faulty and replace the temperature sending unit if necessary.
Read Full Q/A … : Temperature gauge reads a little lower on highway
Gas gauge isn’t working. Sometimes the speedometer and the temperature gauge doesn’t work. Limited lights around gauges and radio.
ANSWER : Hi there. The dashboard lights are burned out in the dash and the dimmer switch could be worn causing the lights to be weak. The gauges that seldom fail to work is most likely a loose wire in the dash panel. The fuel gauge that is not going to E when shutting off the car has a damaged rheostat within the sending unit. The sending unit is in the fuel tank attached to the fuel pump. If you need further assistance with your gauges not working, then seek out a professional, such as one from Your Mechanic, to help you.
Read Full Q/A … : Temperature gauge reads a little lower on highway
Temperature gauge reads a little lower on highway
ANSWER : Hi There,
It sounds like you may have a faulty thermostat. The thermostat regulates the flow of the coolant in your car’s engine and controls when the coolant flows in and out of the motor from the radiator by opening and closing at specific temperatures. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature.
It sounds like you may have a faulty thermostat. The thermostat regulates the flow of the coolant in your car’s engine and controls when the coolant flows in and out of the motor from the radiator by opening and closing at specific temperatures. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature.
Read Full Q/A … : Temperature gauge reads a little lower on highway
My temperature gauge keeps making it look like my car is overheating the temperature gauge moves up to the red. I already changed the thermometer
ANSWER : Hey there. Your cooling system consists of several components. Thermostat, radiator, heater core, and water pump are just a few. Since the thermostat has been replaced, it is more than likely not the cause of the engine running hot. If any part of the cooling system like the radiator or heater are clogged, coolant will not circulate thought the system properly.
If the water pump is damaged internally – the impeller separated from the shaft or fell apart – this also could cause the coolant flow to be stopped. Other cooling system components, such as a bad radiator fan motor, relay, or coolant temperature sensor which sends a signal to the radiator fan to turn on can be at fault. Also, a leaking head gasket can cause the engine to run hot. Have a certified technician diagnose the running hot condition before replacing parts that may not solve the problem as that can become costly.
Read Full Q/A … : Temperature gauge reads a little lower on highway
Temperature gauge does not work – 1998 Mercury Grand Marquis
ANSWER : You will need to test the computer to scan for data of the temperature sensor to see if the computer is reading the correct temperature as tested externally on the coolant sensor. If the sensor is not accurate then replace the sender. If the sender is accurate then you will need to have the temperature gauge replaced.
Read Full Q/A … : Temperature gauge reads a little lower on highway
How do I get the maintenance required light to stop blinking and my temperature gauge to be normal?
ANSWER : Hi there, thanks for writing in. The Toyota maintenance light is a reminder to get your oil changed. This light comes on periodically and needs to be reset with every oil change. As for the temperature gauge this is normal. The engine is cold when it is first started so it reads like this and as it runs it warms up and the gauge starts moving. This is normal. I would just have your oil change done when you get a chance. If you want to have your oil changed, consider YourMechanic, as a certified mechanic can come to your home or office to do this.
Read Full Q/A … : Temperature gauge reads a little lower on highway
Fuel gauge and temperature gauge not working.
ANSWER : The fuel gauge not reading properly may be likely related to your fuel sending unit or the gauge in the dash itself. The sending unit is a small float type component inside your fuel tank that measures the level of the fuel inside the tank. As the fuel level drops, the float level changes and sends a signal to the car’s computer which then displays the reading on the fuel gauge in your dash.
The temperature gauge also has a sensor (or in some cases called a switch) that reads the coolant temperature and relays this information to the ECU which uses this information to control other functions such as the air/fuel ratio during warm up. This also serves to control the turning on and off of the cooling fans when the temperature reaches a specific threshold. When this is not working properly, you may also experience the engine overheating in some cases. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your gauges.
Read Full Q/A … : Temperature gauge reads a little lower on highway
Problem with the coolant temperature gauge.
ANSWER : Hi there. The temperature gauge is not grounding out to the vehicle chassis. Try putting an additional wire on the housing of the temperature gauge and grounding it to the chassis. If this has no effect, then the gauge is not working and would need replaced. If you need further assistance with your temperature gauge, then seek out a professional, such as one from Your Mechanic, to help you.
Read Full Q/A … : Temperature gauge reads a little lower on highway
