here is a run down of my problem. my car is stock except for a koyo rad. i installed the temp censor in the throttle body coolant line. now when im cruising my autometer temp gauge shows a consistant 165~170. the only time i hit 180 today was after a 1~3 gear pull. are my coolant temps way to low and if not what is a safe point to know that the car is fully warmed up?

 

Your thermostat does not open until 180F, I would say that your low readings (74C-77C)are a combination of sending unit location and cheap gauge. Most cars with a Koyo stay around 85C-89C (185F-192F). You do not need to be overly alarmed by the low readings, just keep in mind that they probably are not accurate. You can also look at your double throttle actuator, it does not open until 80C (176F), if this functioning then your temps are higher then the gauge is reading.

 

I would agree with ^^. Also i would say its possible you have a stuck open thermostat.

CAuse i cant imagine temps never going above 180F, especially in northeast summer weather.

 

What would you guys consider a good water temp guage if the autometer is cheap?

 

Defi, Greddy, Apexi, HKS etc all make excellent gauges, I prefer the Defi in our shop cars.

 

I'm not sure if my thermostat is stuck, when I filled the car back up with coolant it did open so the motor could get it's share of coolant. I know that the gauge was working fine when it was in my Fc. I wonder what could be going on.

 

You can always test the temp sender if you really dont wanna change the gauge.

ANd yes DEFI is the gauge i prefer, i have them in my car. Very precise, and looks great cosmetically.

On a side note, i just came back from cruising for about 45 minutes. My temps never did go above 180F, that was because i was on the highway. But once things started to slow down, temps rose.

If your on the highway cruising, it might be normal temps but if your temps stay low in traffic and slow moving driving, then yeah something is wrong.

 

My temps stay really low even when sitting in traffic. How would you test the temp sender?

 

Take everything out and test it in a bowl of water.

Get a thermometer, stick that in there along with the gauge sender. Then give the gauge 12v and ground and compare the gauge readings with the thermometer readings.

 

+1 'cept by bowl i think he means pot and on a stove.

 

lol yeah that too.

I was just thinking of just boiling water, then putting it in a glass bowl. idk

Whatever works though,

 

I don't think there is anything wrong with your gauge or sender. Make sure the sender sticks down far enough into the coolant flow. Also, if you are a little low on coolant, there may not be much flowing thru the TB coolant line. It is the highest point in the cooling system.