so i finished the header install tonight so when i went to start it up it started just fine but the idle isnt quite right and when i go to give it gas theres nothin there. the gas pedal goes to the floor and theres no throttle response. anybody have any idea what might be causing this?

 

Did you unplug anything and forget to plug it back in?
Check any connections in the areas you were working in.........

 

Not trying to bag on you but did you disconnect/damage the cable somehow in the process?

 

the OP's truck is a drive by wire if he has the 5.4...

 

Did you reset the PCM? Disconnect Neg battery cable wait a few minutes and reconnect. O2 sensor wires or damaged sensor? Improper installation causing leak at manifold?

 

i pluged everything back in and didnt break anything also theres no leaks at the manifolds

 

You almost have to of missed something here... I'm not sure what.
Almost sounds like something with your MAF sensor.

 

You had to have left something unhooked.

 

figured it out a pin on one the sensors was bent so the connector wasnt going in far enough

 

Thats good, least it was somthing simple and a quick fix.

 

Glad you found it!

 

now take a breath, then pick your heart up off the floor!

 

Great job on finding the problem.

 

Now how about your results?