The car will start but dies. It won't maintain an idle what should I do?

Hello,

Are you able to keep the engine running if you apply throttle?

If so then the issue could be a dirty idle air control valve (IAC).
The IAC is located on the throttle body (see diagram below)
The IAC controls the engine speed while idling. Over time dirt and debris can accumulate inside the valve and that will create restriction and prevent proper air flow. Which in turn will not allow the engine to idle.

Cleaning out the IAC can improve this idling issue.

https://www.2carpros.com/articles/how-a-idle-air-control-valve-works
https://www.2carpros.com/articles/idle-air-control-valve-service

I have attached diagrams for your reference.

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