Engine stalls at idle early in the Morning when the engine is cold

Hello,

Vacuum leak can lead to the engine stalling when cold. Typically, with vacuum leak the engine will also run rough.
A vacuum leak can be from any of the vacuum hoses under the hood. It can also be from a leaking intake gasket. It is possible that the intake gasket leaks only when the engine is cold as it warms up everything expands and seals the leak.

You can check for vacuum leak at the intake gasket by spraying carburetor cleaner, while the engine it at idle, at the base where the gasket is. If there is a leak the engine will react to the carburetor cleaner and will idle height for a little bit, then go back down after the chemical burns off.

Here is a helpful guide:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please let me know if you have any questions.
Thank you.