How to test ignition coils and their wiring?

I am getting cylinder misfiring OBDII codes after taking the ignition coils and spark plugs out to check for oil deposits on the spark plugs as well as a cylinder leakdown test.

How can I test that coils and wiring are not to blame? Each coil has a connector with, I think, 4 wires, they all look alright and I don't know what else I could have possibly introduced. I never had this code before.

 

If you have any idea which cylinder is causing the misfire you can switch the coil with another one and see if the misfire follows.

 

Yes, I get one generic misfire code out of the OBDII (P0300) and two specific ones (P0301 and P0302), corresponding to cylinders 1 and 2.

 

Switch 1 & 2 with 3 & 4. See if the codes move.

You are likely going to need a high end scanner that can read data streams. Techstream(Toyota) might be the best way of getting it done. All kinds of Chinese people on ebay selling pirated version of this along with hodge-podge cables. Someone here might be able to point you to an an ebay seller whose products work.

Me...I'd just as soon invest in AutoEnginuity. Haven't done it yet, but will one of these days.