Facing the front of the car, it should be a small black plastic box mounted near the firewall on the driver's side with a vacuum line running from the throttle or manifold. It is not mounted directly to the manifold. Granted, that's how it is in my '93 Integra Helms manual and the location may possibly have changed on the newer cars. Here's the pages from my manual which should give an idea of where the MAP sensor is.