Car starting to overheat, no visible signs of leaks. Please help

[Jakeb207]

I am really at a loss on what to do.
I have a 2000 Buick Century 3.1L

About4 Months ago I started noticing I was losing coolant. I finally figures out it was my water pump going out. Got that fixed, Now I have about a million coolling problems that have just come up in about the past 2 weeks and I am really not sure what to do or whats wrong. Here are my symptoms.

Loosing Coolant No visible signs of leaks
No Coolant in the oil
No smoke out of exhaust
Water Pump Replaced (it was bad)
Car overheats while in idle
Heater only works sporadically, sometime the car will be at operating temp but the heater only blows cold air
No heater core leaks
Smell coolant when the car if off and I get out (obviously a leak)
Temp gauge is all over the place sometimes. Hot/Cold

I am about to replace my thermostat, I know thats probably not the issue but its cheap and it couldnt hurt to replace it.

Any help would be great.

[jdl]

Might be a problem with intake manifold gasket? As far as overheating at idle, does the radiator fan run ok? From work already done on it, might be air in the system?

[Jakeb207]

Originally Posted by jdl

Might be a problem with intake manifold gasket? As far as overheating at idle, does the radiator fan run ok? From work already done on it, might be air in the system?

Thanks!
Yes, the radiator fan runs, when It kicks on the gauge starts to go down.
Iv heard about the air in my system, How do I go about bleeding the air out? Iv looked online and it seems easy but I just cannot figure it out.

[danielsatur]

Add a Prestone flush kit, but don't flush!
This kit will allow you to use water pressure to force out air pockets.

[Jakeb207]

Originally Posted by danielsatur

Add a Prestone flush kit, but don't flush!
This kit will allow you to use water pressure to force out air pockets.

Thanks, there was a bit of air in the system

No here is something I noticed eariler today after i got most of the air out.
I drove around and ran some errands and when I got home I popped the hood and I could hear what sounded like liquid seeping out of some place. Best way to describe the sound would be if you put your lips together and try and spit. Youll get a liquidy air bubble sound. Its seems to be coming from right around the area where my thermostat and air intake is. So should I be leaning more towards an intake gasket leaking, I wouldnt imagine if a head was leaking or not.
I really dont know much of anything about the heating and cooling of a car.