I hope you replaced it with 911-617-117-00, not 930-617-117-00
When you say irratic idle, does it hunt? What's it doing? If it runs well when warmed up, it's either cold fuel and air that's out of sych. When did the cold idle issue start? Any correlation to ambient air temp? You may also have an irratic cold start injector, but don't go their yet.
Have you checked that your AAR is closing as it should and not sticking...
You'll have to provide more info.