Intake Gasket Question

[ridiculously_necessary]

Short of removal, how do I find out if my intake gaskets are leaking?

Somehow I have air getting into my coolant, or coolant evaporating/escaping. I have also replaced my radiator cap for measure. I suppose I could have a failing head gasket but I am not experiencing any problems typically HG related. Could a leaky LIM also cause the car not to start or idle without my foot on the gas? I know a cps, tps, and egr can cause that as well. Sometimes its fine after it warms up, and sometimes not. It can happen when the car is cold or warm. I also don't have any coolant in the oil, not visually anyway. Any other thoughts are welcome!

In addition, I don't know if I have a failed t-stat or if this is also a symptom... the car never really warms up and i get a t-stat P0128 code. If it does warm up, its only at idle, and then cools off on the road.

EDIT: Looks like my sig isn't posting, I have an 05 Impala 3.4 200k

Thanks,
Matt

[Purple pit]

Did you clean out your Idle Air Conrtol port? Sounds like the IAC valve is sticking.

LIM can leak on the outside and the inside. Check where the head meets the intake on both ends.

[ridiculously_necessary]

Completely forgot about that. I'll give it a clean. Thanks. I will check the ends as well.

[Purple pit]

Your welcome. I can help on the little things.

[ridiculously_necessary]

So I read today that GM fixed the LIM gasket problem after 2003. Does this mean my LIM gaskets are most likely fine? It is very hard to see, but it appears that i have a liquid puddle in the engine valley, a very small one. But i haven't lost any more coolant in the last three months or so...

[Purple pit]

If it's by the oil pump drive then that is a leaking LIM. Just be sure that the thermostat housing is not the one leaking(there is a small chance of that though, you would see it in other places).
Also be sure there is nothing in the oil. Check the dipstick and under the oil fill cap.