It hooks to a vacuum port on the intake manifold behind the carb.
Code 33 is a MAP sensor code. MAP sensor circuit error (signal is high meaning there is low vacuum getting to the sensor). Check the vacuum line going to the MAP sensor. Its usually located on the side of the breather, usually a green plug with three wires in line.
The Vacuum line usually connects to the brake booster , or atleast it does in my Ford explorer
Bad fuel pressure regulator, Map. sensor not working or the vacuum line is bad or off of the sensor. You did not say what year it is.
The vacuum line diagram on a 1985 Chevy Pickup can be found in the service manual. It details not only the location of each line, but its function as well.
There should be a vacuum line diagram on the passenger strut tower on your Celebrity.
Passenger side of engine next to throttle body. It is the senor with the vacuum line running to it.
Vacuum lines on the 2003 Chevy Silverado 2500 heavy duty pickup truck. A diagram of the entire vacuum line system can be obtained from most Chevrolet dealerships.
The vacuum line diagram for a 1997 Chevy Venture 3.4 engine outline where each line goes and what it connects to. It can be found within the service manual.
The vacuum hose line routing diagram can be obtained from most Chevrolet dealerships. Obtaining a diagram will be the easiest way to visualize vacuum line routing.
You can find heater vacuum line diagrams for your Chevy van in most Chevrolet service manuals. The service manuals can be found at your local library.