1997 JETTA GT TEMPERATURE GAUGE FLUCTUATES FROM 195F TO 205F WHAT SHOULD I CHECK

Sounds normal. If the gauge moved further over, it would indicate an overheating problem, wouldn't it? Check that engine is at normal operating temperature after it warms up. If it is running too cold, your thermostat might be stuck open.

I can't remember what mid-temp is supposed to be but I find that my 97 Jetta doesn't get up to half way or even near it most of the time. If you are talking about interior heating and your temp gauge doesn't get anywhere near half I'd say that you have a thermostst that doesn't want to close and is keeping it too cool so you're cabin doesn't heat up. I'd recommend thermostat replacement. I still have to change mine and it gets luke warm at best in my car most of the time.

try skewing the engine coolant temperature sensor with a multi-meter and a temp vs resistance or voltage chart. the ect could be out of range and not set a code. also check actual engine temp with an infrared thermometer. hope this helps

There is two sensors-blue for fuel mixture preparation & black with 4 pins for a gauge and overheating control.You told me that you has been change all sensors.Did you put new ones? Also check for engine coolant level sensor on a white plastic tank. there is not another reason for LED to blinking.

Definitely check your fluid level in your radiator. Top it off all the way. I've seen that happen multiple times on cars that were low on anti-freeze. If that doesn't work try replacing your thermostat. It's cheap and the easiest place to start if topping off the fluid doesn't get you fixed up.

195 degrees is the typical high end on the thermostat (when the thermostat opens), so the temp gauge should read a max of 195 degrees, give or take a few degrees. Some people replace their thermostat with a lower temp one, such as a 180 degree one. Then the gauge will read lower (approx 180 degree max). So the range is typically from cold at start to just under 200 degrees.

Check your cooling fans to insure they are working to cool the radiator...

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I suspect you need a new thermostat. It should be running at 195 degrees F.

If the engine does not fully warm up, the engine can not go into emission control mode.

The engine temperature sensor sends a signal to the engine/emissions computer that the engine is now at normal operating temp. The computer then starts controlling fuel flow, EGR, etc. so that emissions are being controlled.

When the enigne is cold, you are in what we call "open loop" meaning no emission control.

Get the thermostat installed first. Make sure it's the same temp rating as the one that's in there. Either 180 degrees or 195 degrees.

Then you should pass.

Check and/or have the coolant temperature sensor replaced.

How does the temperature gauge read on your dash.. Is your car temp at 190 degrees while driving.. If its higher than 190 your overheating and that would cause the fan to cool her down.. good Luck