Where is the drain plug for coolant system on 1999 Plymouth Breeze 2.4 DOHC. Or do I just disconnect hose at bottom radiator. All I want to flush the system and replace coolant.

A temp sensor information is used for all kind of things even on 1999 vehicle . The PCM/ECM -engine computer use temp info for fuel control strategy , turning on the radiator cooling fans , information for the temp gauge . The temp. sensor really doesn't control anything , it's a input to the engine computer , the engine computer controls thing's . How Engine Coolant Temperature Sensors Influence The Modern Powertrain

Check the cam cogs or the cam., on pulley and cover pointer.. check front pulley for top dead centre mark

either your thermostat is out or your water pump

The area behind the drain plug on the radiator is likely plugged up with debris. Removing the lower radiator hose will do the same thing and a little faster. You also run the risk of the drain plug leaking if you remove it. Removing the lower hose will prevent this from happening as well. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

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The Drain **** is located on the bottom Right (passenger) side of the radiator. Turn counterclockwise to drain. Do not turn drain **** more that 1/2 turn or damage may occure. NOTE: To open draincock on vehicle equipped with 2.5L engine, use a 3/8 inch drive extension 3" long, a 19mm socket with universal. good-day !

your car sounds like its low on anti freeze or air locked

Thermostats almost always reside in a housing at the engine side end of the upper radiator hose. Drain coolant first, then loosen radiator hose to access thermostat housing. If you can't find the housing, consult your vehicle service manual for location.

WITH THE ENGINE COLD.
Open the radiator cap. The thermostat in down inside about 2 inches. You may need drain some fluid off to see it. You will have to remove the radiator cap holder, - 2 bolts to remove it. Install new unit with new gasket.

Automatic Transmissions normally won't have a drain plug. You have to take all the pan bolts out and lower the pan to drain the fluid. you will make a mess!!

Just by a bottle labelled "power steering fluid" at local parts store, you'll be o.k., just don't let anyone talk you into using transmission oil as substitute.