Almera 2001. Temperature gauge shot up to red while driving, but car didn't seem to be overheating. When gauge was high, engine lost power.

Reasons the Temperature Gauge Reads High

If the temperature gauge reads high, it could mean your engine is overheating. Another reason your reading might be high is you could be losing coolant. A small leak or evaporation may cause your radiator to slowly lose coolant. A third reason your temperature gauge reads high could be because the thermostat is broken. If this is the case, you may need a coolant temperature switch replacement. The last reason the temperature gauge could read high is because of a water pump, or water pump gasket failure. If the water pump is malfunctioning, it may need to be replaced by a professional.

What to Do If Your Temperature Gauge is High

If your temperature gauge is reading high, it means your car is overheating. This is a very serious matter and you should never drive an overheating car. If your car starts to overheat, shut off the air conditioner and open the windows immediately. If this does not reduce the overheating, turn on the heater as high as it can go. If this still doesn't work, pull over on the side of the road, turn off the engine, open the hood carefully, and wait until the vehicle cools down. Never open the radiator cap while the engine is hot - coolant can spray and burn you. Once the vehicle has cooled, take the car to a mechanic right away so they can diagnose the problem. Cars are especially susceptible to overheating in hot climates, like what's common in cities like Los Angeles, Phoenix, Las Vegas, or Atlanta.
The temperature gauge is an important tool in your vehicle that shows the temperature of your engine's coolant. Contact YourMechanic and have your car inspected for overheating if it reads too high, as this can cause serious problems...

Reasons the Temperature Gauge Reads Cold

On most vehicles, the temperature gauge reads cold until the engine has run for a few minutes. If the temperature gauge still reads cold after the engine has warmed up, the gauge may simply be broken. Another reason the temperature gauge could read cold is if the thermostat in the vehicle stays open. With the thermostat stuck open, the engine can be overcooled, causing a low temperature reading. If this is the case, the thermostat may need to be replaced.

Chevrolet Venture Questions - My thermostat gauge in the ...

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CarGurusOct 2, 2014 - My thermostat gauge in the car is going up and down, what could be theproblem - My thermostat starts on cold and when i get in and drive it goes from low .... low to almost hot., and it jumps back and forth when I drive the car.

Temperature gauge shot up - Bimmerforums

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Nov 30, 2010 - This morning I had a problem starting the car as it was -22F and when I finally started it my ... Now the temperature gauge still jumps right to the red zone (all the way to the right). There is no way that this is right as the engine is cold. ... Even if it were stuck closed, it would take a while for the car to warm up.

Car Repairs: Coolant Temperature Gauge - YouTube

? 7:47
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Apr 15, 2012 - Uploaded by TheYoshiClan
... Caprice/Olds Delta 88 owners. If your coolant temperature gauge isn't working, check this out before heading out to get replacement parts. ... the car is barely getting warm inside. What seems to be the problem if you know?.

My car temperature gauge keeps bouncing around from cool to red ...

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I'll put my bets on a faulty gage...but that's just me.

Well you've lost power to one or two major circuits. Could be a problem with the key switch or a major fuse in the engine compartment.
I would check the fuses for power and find out which ones are dead then go from there.

Usually the problem with no heat and overheating is low coolant, thermostat, or a faulty water pump impeller.
The radiator may not be full of liquid coolant, or the pump may not be moving the coolant thru the block.

If your temperature gauge is reading too high, it can only be one of two things: The engine is overheating or the gauge is "lying" to you. I would recommend first taking the temperature of the cylinder head with an infrared thermometer to determine which one it is. If the engine is actually as hot as the guge says it is, then you need to check your cooling system. If the engine is not as hot as the gauge says it is then you need to diagnose and repair your gauge circuit. (most likely an inaccurate temperature sensor)

FLUSH RADIATOR, HEATER CORE AND ENGINE BLOCK.ADD 50 / 50 ANTIFREEZE AND WATER ALSO REPLACE RADIATOR PRESSURE CAP.IF TEMPERATURE GAUGE STILL STAY HIGH THE ENGINE COOLANT TEMPERATURE SENSOR COULD BE FAULTY.

jtg

Look for a loose connection to the temperature sender unit on the motor.
If all connections OK, you may need a new temp sender unit.

sounds like a faulty sender unit not passing the right voltage which is causing the gauge to read high