1993 Nissan Truck engine surge

Ok what I need you to do first is check for any vacuum leaks. So check the vacuum hoses first and check for any cracked or broken hoses. Also check the PCV hoses for any cracks. If that checks out good then I need you to get a spray bottle with water in it and while it is running spray around the throttle body the upper intake and the intake manifold itself too. What you are looking for here is a change in idle as you spray looking for any vacuum leaks in the gaskets. Here is a vacuum routing diagram to help with locating all the vacuum lines. Lets start here and take it from this point. Let me know what you find.