Why do I Have 2 Different Water Temp Readings?

[Seriph]

It appears that I am running a little warm...Why would my stock instrument cluster gauge register a normal reading for water temperature while my aftermarket pillar gauge registers the water temperature at around 220 degrees ? It will very rarely go beyond 220 degrees as I am driving around or idling. Car does have a new thermostat as well as water pump. Radiator hoses are good, no leaks. After market gauge sensor is on top of the T-stat housing. Any advice is greatly appreciated.

 

[synthetek]

It appears that I am running a little warm...Why would my stock instrument cluster gauge register a normal reading for water temperature while my aftermarket pillar gauge registers the water temperature at around 220 degrees ? It will very rarely go beyond 220 degrees as I am driving around or idling. Car does have a new thermostat as well as water pump. Radiator hoses are good, no leaks. After market gauge sensor is on top of the T-stat housing. Any advice is greatly appreciated.

The stock gauge reads from a different sensor and its not very accurate, in both of my 2g the stock gauge always just sits at 1/2 way but if I log it ecmlink or assign it to the boost gauge I can see that it goes higher. Don't trust the stock gauge.

 

[ileagle95]

Until you get around 225*ish is when the needle will start rising. And stock gauges are useless. If your aftermarket gauge us a descent brand is trust that more.

 

[Seriph]

Its a VDO gauge . Well the VDO gauge has been to 225 degrees before and the stock instrument gauge never rose for some reason...hmmmm. I do notice my upper radiator hose is pretty warm, but I don't know if that has anything to do with it. Also, its not to the point where my coolant boils...yet .

 

[synthetek]

Its a VDO gauge . Well the VDO gauge has been to 225 degrees before and the stock instrument gauge never rose for some reason...hmmmm. I do notice my upper radiator hose is pretty warm, but I don't know if that has anything to do with it. Also, its not to the point where my coolant boils...yet .

I would trust the aftermarket over the stock one. If you get a logger you can check and see what temp the ECU is seeing.

 

[ileagle95]

The stock gauges are more "guestimates" than accurate. That's why their really pointless.

 

[Seriph]

Another small piece of info...it takes about 20 minutes to slowly-gradually climb to 220 degrees.

 

[jbeaton9292]

Well stock gauges in the dash are more of a guestimation on your end being that there are just lines that the needles sits between where the aftermarket gauge is gonna be way more accurate being that it has more numbers with the smaller lines being numbers between the other two numbers and you can get almost exact