Yes they do at the intake manifold.
The intake manifold are very bad about corroding a hole in them which means that you will have to replace it.
Intake manifold at top of engine?
There is a heater hose that goes to the left rear top side of the intake manifold and that fitting leaks engine coolant sometimes and it will run down the back of the intake around the distributor. If that fitting is not leaking then the intake manifold gasket is leaking coolant in the corners of it. REplace the intake gasket. That's all that can leak coolant on that year engine. If coolant is leaking out between the transmission and engine block then you have a freeze plug leaking in the back of the engine, between the transmission and block. Must remove the transmission and flywheel to fix it.
under the intake
Look for leaking antifreeze/coolant. Usually you can see it leaking around the top of the engine. Also check your oil, if it looks milky it has been mixed with coolant and you intake manifold gasket is leaking. That being said, it is possible to have a leaking intake gasket with no sign of leaking antifreeze. Most intake manifold issues/leaks are coupled with poor engine performance and even sputtering and lack of power.
could be freeze plug, or intake leaking
Mounted in the heads.
Check to see if there is coolant on the engine block. It is common for the Monte Carlos, along with other GM cars equipped with the 3400 V6 engine to experience leaking intake manifold gaskets. A leaking intake manifold will cause oil to leak into the coolant system and even worse, for coolant to leak into the oil system.
Intake gasket leaking on the inside of engine.
It is very common. The intake being made from plastic gets brittle and fails.
Need to check the 4 corners on the intake manifold. It is common for the intake to leak engine coolant.