Your code and condition indicates you have a vac leak.
However , the reason we start with the correct plugs and the coil connectors is b/c without a scope, they are hard to diagnose , so this is one of the few times it is best to change them [ specially the connectors, due to their failure reputation and low cost]..
Look for a leak, but I would still start with the 3 connectors under the coils..
You can not look at a coil connector and see if it is good/bad.
You have a Scope?????