Just recently my car has started to idle insanely low and will not run smooth at all when it is cold. Getting it hot, I am worried I am going to kill the car. At first I thought that the choke was just stuck, so I loosed it up with some cleaner and brought it back from full open to work with the spring. That helped but now the car does't runs smoothly anymore and its not enough just to bring up the idle with the spring. The carb is a holley 4150 but I am not sure what is really going on...

vacuum leaks perhaps.. bad gas? misfiring on one cylinder maybe? how are the plugs? is your timing and electrical system ok?