Try a minor tuneup by changing the spark plugs and checking the distributor contacts. Sounds like the vehicle is burning rich which is what's making it shake and finally stall while stopped. Dirty or worn out plugs or even a bad spark due to corroded or dirty contacts in the distributor will cause this.
Check the air filter to see if it is stopped up. Check all the vacuum hoses for a leak. Replace the PCV valve.
It has a vacuum leak or the IAC is faulty.
I have a 1989 929, when its cold it runs real bad but once warmed up it has problems idleing, the car shakes and sometimes when stopped it stalls, mine is an auto, but when driving like on the highway it runs fine. Is your problem similar?
My best guess is that the Idle Air Control (IAC) valve may need to be replaced.
check your idle controle moter. it is probably crudded up or not wotking.
Check the computer diagnostic codes. You can usually borrow, rent or buy a code scanner from most auto parts retailers.
Change the spark plugs and wires first. That is often all they need to run right.
What causes a 1997 Pontiac sunfire gt with a 2.4 liter engine to stall when stopped at a light
engine stalls sometimes driving
Many possible reasons, vaccum leak, timing belt breaking, bad alternator, bad battery, etc., need more information.
If this was my vehicle ,I would replace the control module which is attached to the side of the distributor. They are known for this problem. I hope this helps you. Mark
check the vaccums lines like the PVC valve to see if the hoses are cracked and need to be replaced or not.