Is there a way to test if a distributor is working? I get spark on cylinders 1 & 3 but not 2 & 4, replaced spark plug wires and got a used distributor, but the distributor wasn't known to be in working condition or not. Maybe my ignition coil or ecu are the problem?

I know this isn't FI specific, but my problem is on an FI car and this section gets more eyes.