N14 celect plus erratic idle

[SemiSweet]

I had one hunt at idle and the ambient pressure sensor was the issue. But didn’t move as much rpm as your stating. It was at a default pressure which didn’t change even when unplugging. Not sure if yours is the updated sensor which is much smaller and just zip ties to the harness instead of mounting on a bracket to the block to the right of the ecm. The wiring on those n14s can be terrible as well. Did you check or replace all the injector pass trough connectors and verify the harness plugs were not stretched out causing intermittent connection.