high revs during start

If my intake manifold gasket was leaking, which is what you guys have been telling me, does it make sense that sometimes when i start the car it will occasionally start right up but the rpms are at 2,000? Sometimes it hard starts where i have to start it 3 or 4 times then hold the gas pedal down slightly till it finally hold an idle and other times it revs really high and slowly goes down. If it revs high though it will still idle slightly high for the first few minutes i am driving around. Like if i pull up to a light it will sit at 1200 or so and accelarate once i let off the brake. But the problem seems to go away once i drive for a little while. let me know what you think before i have it looked at because i dont want to fix the manifold gasket and have something else be the problem.

If you are taking it to a place to be fixed have them leak check it. they will start the truck and then spray the area with carb cleaner (or even water vapor).