Alex may be right. The KA I swapped into my car was a '96 motor and I swapped the intake mani for a '91 unit. The '96 motor is OBDII which is why this was required. I believe the '95 motor is still OBDI unless its a late model '95. I know Andrew from this board swapped a '95 without swapping the intake mani and had no problems.
I think you should sort out your vacuum leaks first and go from there.