Why is my 2000 Ford Mustang Overheating?

I have a 2000 Ford Mustang v6 3.8L Base. I will start describing what happens when you start the car: The car shakes and you can hear kicking/popping noises from the mufflers and in the front of the engine. When you start to drive, it shakes and kicks struggling to drive for several miles. When it reaches operating temperature it seems to run normal, but then it overheats really quickly. This always happens in the city (at red lights) but it seems to run normal on the freeway. I have replaced the thermostat, radiator and radiator cap. Recently I changed the Secondary Air Injection Pump from the junk yard. This last time it overheated, it spit out liquid and there was so much pressure built up in the hoses (the pressure never goes away even after the car has been sitting for days). Also the coolant always turns a little orange. I've flushed the system before because it was deep brown.

Sounds like a CTS… Coolant Temp Sensor… Problem and possibly bad cooling fans or related circuit issues. Do the cooling fans come on when it overheats? If the CTS is defective and tells the computer via improper voltage readings that the engine is hot when it's really cold, then the computer will adjust for improper fuel injection pulses… Too lean… And the engine may run rough until the engine warms up. A faulty CTS may not trip a trouble code/CEL light and due to faulty readings from the CTS, the PCM also may not kick on the cooling fans when needed… Causing overheating in city driving. Or you have other issues with bad cooling fan motors, bad fan relay, blown fuse for the circuit, etc. Have a shop test the CTS and cooling fans/circuits for proper operation. Bleed the cooling system of all air pockets if needed as well.