Okay so I bought a Monte Carlo just about two months ago. It was running great until about last week where I noticed it was leaking a fair amount of coolant. At first I thought it was the water pump so I went and bought a new water pump and serpentine belt. Replace them and it still leaks. I have no idea what the problem is. The leak is coming from the front passenger side of the car. While driving the temp gauge goes up to maybe 50% but then falls to maybe 10-20%. Let me know what you guys think

 

didn't see what engine you have or how many miles is on the car?
Alright a few things to check.
Front passenger side could be
1.the overflow hose is bad or the clamp is off.
2. Radiator Cap is not on tight
3. The radiator hose maybe bad also. ( if they feel spongy when you squeeze them) it might be a good idea to replace them.
4. Intake manifold gasket could be bad too.
5. Check the heater hoses also

 

3100 motor 158k miles. While Erving the car with hood up the front left hose pinched together so I got a new hose and will install in the morning. Will keep updated