Volvo: volvo s40 1.9t, temperature gauge, volvo s40

Question

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-----Question-----
I have a 2001 s40 1.9 t and recently it began running with the tempature gauge high on the red mark. I originally thought it might be the thermostat and took it out and am running the car without one.....The car runs with the tempature gauge on high then all of a sudden it goes down....Then back up and so on....I know all the fans are working because you can not only see them but also hear them...... I know the car wont completely overheat because ive let it get as high as it could and it never even feels like its running hot? Do you have any idea what this could be? the car currently has 124 k miles. If you can please email me at echeverriaalexis@yahoo.com
-----Answer-----
Alexis,
The engine is designed to run with a t/stat. So put one back in. If the car has no sign of overheating then there is a possibility that the gauge or sending unit is causing the overheating reading on the gauge. If you have a Volvo scanner then you can read the tempature of the engine. That you can compare to the gauge.

Im sorry for bothering you so much but this is the first time owning a european car and im a little nervouse about the negativethings versus the positives ive heard about them..... will the car eventually get even more damaged if i run it without a thermostat?  is the sending unjit or temperature gauge expensive to replace? if u have any additional information about this car that can be useful id relly appreciate it .....thanks a million.

Answer
Alexis,
As with all repair work these days things are costly. When  you go to a shop they will first have to go over all the things that have been done so they know all things are good and right. They will need the car for some time to preform the diagnoses on it. All this time means hours of work on the vehicle. You must be certain that the engine is not overheating, because if it is then there is a greater threat of doing more expensive damage. So I urge you to get the problem looked at now so you do not do further damage. The late model engines do not do well when overheated.