Hello recently my 06 scion tc as been overheating I had changed the thermostat and I had gotten it bleed but the car overheat gauge is still going into the red and now my reservoir is empty I don't know what the problem can be I am thinking about changing the ect but I don't know how to properly test it and I'm getting no check engine light. I will greatly appreciate if anyone can help me thanks

 

I hate to tell ya this but from what you describe its sounds like a head gasket to me.

 

That what I was thinking but I spoke to a mechanic and he told me if it was the head gasket the engine would be smoking up also I would see a lot of smoke coming out from the tail pipe. But on the highway the gauge go up to the red but it comes down and stay there but it overheats in stop and go traffic

 

Check to see if you have a leak anywhere from the hoses, radiator, water pump, etc. Never let it get up to red on the temperature gauge, because eventually you'll warp the head along with the headgasket if you keep letting it overheat and you'll end up spending more money than you should have in the first place.

 

The only thing I.saw.leaking fluid.is in the bottom of the car by where the exhaust pipe starts from the motor

 

You could do a leakdown test or let the car cool down, take the radiator cap of, turn on the engine and look for bubbles. There's going to be flow because of the water pump, but it gives u an idea. With the leakdown test u could see the bubbles coming out of the radiator as wel

 

Forgot to ask, did you verify that both fans are coming on?

 

One of the two fans are coming on also what do I need to.do a leak down test

 

If only one fan is coming on, that might be your culprit. I had a same scenario nearly two years ago when the electrical connector came undone on one of them. Driving around without stoping or highway was fine, until I got stuck in bad traffic. The niddle just kept climbing and never went back down, until I rode nonstop for a good 10mins

 

^ i aslo second that idea. since you say its in only stop and go traffic and you might no be getting enough cooling efficiency.