Won't start unless gas pedal is held down

I replaced the intake manifold gasket on a 94 intrepid 3.5L and now it will not start unless I hold down the gas pedal. If I let off the pedal the engine dies. It doesn't run well at all when i am holding down the pedal.

There isn't any black smoke coming from the tailpipe so i don't think it's flooding.
I listened for vaccum leaks holding a large hose to my ear.
Each plug seems to be firing because the idle drops when unplugged.


any thoughts on what might be causing the problem.

Have you found a fix for this?