Ive had issues like this when adding parts etc.
Before you look to far you should reset your ecu. Remove Negative and pump brakes ( they will firm up after several ). Reconnect and your ready to go. Remember it takes several key cycles and around 100km before fuel trims etc settle down.
If you still have probs I would look at your Cdfp. I had the same issue in 3rd at the same revs when I had the Piasini v3 update. It eventually settled down alot but I upgraded my pump and all was fixed.
Cheers Aaron
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