Coolant leaking
 

Hey folks

97 4.3L Coolant is leaking, not sure where but seems to be back side, passenger side like above the starter. Strange part is it only seems to leak when the t-stat is closed. WTF could this be? Freeze plug? Block drain? Head gasket? LIM?

Thoughts?

Your list is pretty thorough. Heater hoses run in that area also. I'm hoping it's as cheap and easy to get to as that.

99% Sure it's not the heater hoses. Dry where they connect to the heater core ant teh heat kicks @ss stat open or closed. Not ruling them out completely and worth a look see, thanks

sounds like the infamous leaky intake gaskets...

Does the LIM stop when the stat is open? I honestly don't know.....have never had this happen

Usually no, it's a constant seep, but anything is possible...

sounds like the intake gaskets to me. That is where mine was leaking but on the other side. I would recommend getting some UV dye and putting it in there. That will make it very easy to see with a UV light.