OBD shows normal temp dash gauge shows overheating

[nando]

02/2003 Subaru Legacy B4 BE 2.0ltr EJ206 F4 16v DOHC Twin Turbo MPFI model
I have had this vehicle for 2 years and never had any problems.
lately, I noticed while driving for one 1hour or so that the temp gauge moved to red, and within seconds
moved back down to the middle.
so occasionally now does this, took it to a mechanic who used a scan tool to check live data and what temp
The car is running, and he said temp is normal gets up to 203F, the fans come on and drop to 188F, and he says it is possible the temp sensor is on its way to replace it.
was quoted 500 dollars, at the moment I can't afford to pay that much money.
I watched a few videos on YouTube on how to replace a sensor very simple job.
bought the sensor from Supercheap Auto to find it doesn't work for my car Tridon Coolant Temperature ECU Sensor - TCS125, tried online eBay/amazon, ad states my vehicle.
I installed it and this is what happens.
start the vehicle after 1 min dash gauge goes 1/2 way within 2 min needle moves to red got a scanner on to obd port checked live data and temp only 150f put my hand on the radiator hose only warm.
3 sensors I buy doing this. checked Subaru parts sensor not available for my vehicle.
only 1 place I found but not sure it will do the same as the others

https://partsouq.com/en/search/all?q=22630AA161

put my old sensor back in and have no problems only occasionally needle goes up and drops down.
is it possible my dash gauge is at fault or is it a temp sensor?

 

[nando]

02/2003 Subaru Legacy B4 BE 2.0ltr EJ206 F4 16v DOHC Twin Turbo MPFI model
I have had this vehicle for 2 years and never had any problems.
lately, I noticed while driving for one 1hour or so that the temp gauge moved to red, and within seconds
moved back down to the middle.
so occasionally now does this, took it to a mechanic who used a scan tool to check live data and what temp
The car is running, and he said temp is normal gets up to 203F, the fans come on and drop to 188F, and he says it is possible the temp sensor is on its way to replace it.
was quoted 500 dollars, at the moment I can't afford to pay that much money.
I watched a few videos on YouTube on how to replace a sensor very simple job.
bought the sensor from Supercheap Auto to find it doesn't work for my car Tridon Coolant Temperature ECU Sensor - TCS125, tried online eBay/amazon, ad states my vehicle.
I installed it and this is what happens.
start the vehicle after 1 min dash gauge goes 1/2 way within 2 min needle moves to red got a scanner on to obd port checked live data and temp only 150f put my hand on the radiator hose only warm.
3 sensors I buy doing this. checked Subaru parts sensor not available for my vehicle.
only 1 place I found but not sure it will do the same as the others

https://partsouq.com/en/search/all?q=22630AA161

put my old sensor back in and have no problems only occasionally needle goes up and drops down.
is it possible my dash gauge is at fault or is it a temp sensor?

has anyone had a similar experience how did you fix it?
any help please

 

[pfarmer]

has anyone had a similar experience how did you fix it?
any help please

For my 2015 Impreza before I traded it in the thermostat was stuck. While the fans would curb the occasional highs the car's heater controls were enough to take it too cold.

 

[nando]

ok purchased another temp sensor now this one goes to the middle.
leaving the car on idle for 30 min plugged my scanner checking live data in water temp.
when temp gets to 195f needle goes up to the next line check the picture.
it doesn't go to red .temp goes to 203f fan turns on and drops temp to 196f.
now the needle goes to the top line and then comes down to the middle constantly.
I have done gases in radiator check and the fluid doesn't change color