Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Temperature Gauge Fluctuates

I’ve Hyundai Sonata 2011, In temperature Gauge, it has total 12 bars and normal temperature is 5 bars (it always stays there).
Today’s morning, when I started my car after night. It’s my usual to wait for temperature gauge to reach at five bars and it takes usually 2 to 2:30 minutes to reach but today it stayed at one bar, so I just put my car in drive and start driving, I noticed that the temperature bar goes to 5 bars in seconds and then comes back to 1 bar then then again goes to 5 bar within few seconds and then stayed there as normal, and I noticed this thing two times today after cold start.

I want to know the possible reasons of this, though the temperature bar didn’t exceed the normal limit which is beyond 5 bars, still it’s not normal as I’m living in Saudi Arabia and here these days temperature goes up to 47 degrees so I’m just curious about temperature.

I’ve attached the picture of my temperature gauge at it’s normal state “5 bars”.

Have you checked the coolant level in the engine?


Yes, everything is normal there, no issues.

I’m wondering if the sensor that sends the temp to the display is bad…

Then you might want to have someone check if the coolant temp sensor is working correctly with a real time scanner.


It does seem like an electrical fault of some sort. the sensor, the wiring, the display all could be at fault.

PS, it’s better for the engine if you just start driving instead of waiting for it to warm up.

There is no reason to do that. Just give it a few seconds to circulate the oil and drive on.

Have you solved any of the other problems this vehicle has. If not , it may be trade time.

I would guess the fan kicks in early because it’s freaking 116 degrees F there, and that helps cool it off just enough to drop it 1 “bar,” and then it heats up again and is warm enough not to drop one bar when the fan comes on again.

Those temp gauges aren’t precision instruments. There’s a decent amount of temperature span between the 5th bar first coming on and the middle of the 5th bar’s temperature range.

I also agree with @VOLVO_V70. A few seconds is all you need. No need to warm them up.

He said it dropped to 1 bar and back.

Well, some are solved, right now the car is running good, but I’m planning to sell at the end of this year as ODO meter is around 260K km now, and thinking to buy Pre-owned Ford Taurus 6-Cylinders or Toyota Camry not more than 3 years old any suggestions about this?

Have it inspected by a mechanic prior to purchase, having records of previous maintenance done is a huge plus as well.

Do you’ve any personal experience with any of mentioned car? I’m planning to buy pre-owned car from ford or toyota company itself.

Not many of us here have any knowledge of Saudi Arabia. But here in the US you don’t buy used from the manufacture. I think you mean dealer used vehicle lot. Some decisions you just have to make on your own. Also with the problems you have with current vehicle why wait , trade up now if you can.

My newest car is a 2009 Ford Focus…I tend to buy older cars then run them until they die. Like @VOLVO_V70 said, most of the members on this forum do not have any knowledge of cars and manufacturing standards of cars in Saudi Arabia. Are there any car forums specifically to Saudi Arabia? They would be able to answer those questions better.

Toyota is one of the best selling cars in your country and there is a reason for it. Reliability, cosmetics and comfort. When I was there a few years ago, the streets were littered with Toyota Camry. Ford is not that popular, except for the Ford Explorer. Both are good cars and you should not have any problems finding competent mechanics.

Hopefully the problem will not return but if it does I would first look for a faulty connection at the sensor. It could be the sensor itself causing the trouble but a simple bad connection is the most likely cause of the trouble.

I think your choice of cars is good and would be happy with either one. I would prefer the Toyota myself and you will most likely have to spend a little more for one over a similar Ford model.