When My car started sputtering it was the connection on my TPS coming loose. The locking tab is broken on my harness which is falling apart.
Im definately going to get a good one on vacation to bring back and swap.
If your certain about your vacuum, put a vacuum tester on the car anywayz just to be sure on the T connection behind the intake manifold and see what it does.
This is a pretty good idea of what you will see when you put the guage on and basic diagnosis for the readings.
http://autorepair.about.com/cs/troub.../aa112401a.htm