Rough idle, feels like it's going to stall sometimes.

The engine runs mildly rough at idle. Sometimes if the ECU picks up enough misfire counts it will disable that cylinder fuel injector and it runs a lot rougher then. Bank Two is picking up misfires in the misfire counter, mostly just cylinder 4. There is a mild popping through intake at idle. All SIDI fuel injectors and spark plugs have been replaced by another workshop.