Coolant leak

The intake gasket is a definite possibility. A fairly easy way to look for it is to pull a couple of spark plugs out. If they are really really clean looking, then you know coolant has been getting into the combustion chamber. Here is a guide on replacing spark plugs: https://www.2carpros.com/articles/how-to-change-spark-plugs

Also, just because the oil is not milky does not mean that the head gasket is not leaking. There is a very specific test that looks for exhaust gases in the coolant. Here is a how-to guide for it: https://www.2carpros.com/articles/head-gasket-blown-test

My opinion, you have got to run these tests. The one for a leaking intake gasket is free, so start with it if you can. Good luck and let us know what you find.

When the engine is cold it might not show a head gasket leak, when the engine is hot it expands some. That may be why the shop may not have found it. I agree that it may be a intake manifold leak. The other leaks would leave a tell tale sign of a leak if it was anything else. Does the engine look dry in all the spots you can see?

Hello,

I have seen where the water pump will only leak when the engine is running can you confirm the weep hole is dry?

https://www.2carpros.com/articles/car-is-leaking-coolant

Please run down these guides and diagrams and report back

Cheers, Ken