I am having idle issues with my car after it warms up.
The idle control valve is the most likely cause and is the most common of problems with the vehicle for a low idle problem. You may also need to clean the throttle body and its passages with the idle control valve. I recommend you have a qualified mechanic, such as one from YourMechanic, check over and diagnose your issue with your car. You should also do any tune up maintenance at the same time like filters and spark plugs. The distributor on these cars are also a known problem causing stalling when they get hot and may not allow restarts.