1) Check for any fault codes.
2) Check the connections at the battery.
3) How old is the battery?
2) Check the connections at the battery.
3) How old is the battery?
Now that I know the low voltage primary circuit goes to ground through the mounting bosses I think corrosion on the mounting bosses was the problem. When I got the new used coils I examined them and noted the right hand coil had slight rust staining on the rear most boss and I noted "I wonder if the OEM right hand coil for cylinders 2 & 4 has rust stains like that?". This is what I found.....the original RH coil had a lot of rust and the rust pitting had pretty much destroyed the smooth metal finish the bosses have when in good condition. The LH side does not have the SS U-shaped clip washers and the LH mounts were in original good condition. The washer must be a different alloy of stainless and the combination of heat and electro galvanic corrosion from dissimilar metals causes the RH mounts/grounds to rust.
I cleaned and buffed up the new used one before I installed it.
If you have a high mileage 1300 you might want to check the coil mounting bolts for corrosion that may cause the coil to quit working under the "wrong" conditions.
It's easy to clean up the corrosion - why not do that and reinstall it?