If the engine starts and runs fine at idle for at least a little while then you could drive with the bad idle air control valve.
If the idle air control valve is completely faulty then your engine will usually stall right after you start it up or may stall after you let the engine run for awhile.
So you could be driving down the road and the engine stalls at a stop light or somewhere else when you have the engine idling.
Another symptom of a bad idle air control valve is irregular engine idle speed which can be that the engine revs up too high and then back down.
Usually the vehicle will run fine at higher RPM when going down the road when the Idle Air Control valve is bad but then stall at idle.
If you do have a bad idle air control valve it's best to change it out so that you don't risk getting stranded and improve your engine performance as well.