check engine light

The check engine light on this car will not go off. A while back a clip on the distributor broke. So I got a used distributor popped it in and the car runs fine. Before it used to be really jerky and felt like it was going to stall whenever I tried to take off. the light was never on before. My friend has an OBDII scanner. The car is not compatible. I have tried unplugging the battery, something about a paperclip and poking them in the holes, even my mechanic plugged the car in and the computer reads communication errors. I am trying to sell this car but it's pretty hard to get a decent amount of money for it with this light on. The car runs fine but I know it won't be long til something else comes up. Also, the left front wheel has had this chronic noise. Comes and goes. Seems like these cars all have the same problems, so if anyone could help me out......

You need an OBD I if your car is older than 95. Advance Discount Auto Parts read mine for me at no charge.