I just installed a NX plate kit on my 08 Mustang GT. I put it all together, and now I hear a whistle under load under throttle. Sounds like a vacuum leak to me, and I'm figuring that its coming from the plate/throttle body/intake manifold area. Am I supposed to use RTV as well as the supplied gaskets? Am I supposed to leave the orange gasket in the intake?

 

Just use the 2 supplied paper gaskets and remove the factory throttle body seal
Make sure the screws hoding the NX plate are tight. Mine were loose and leaked fuel
Make sure the plate is flush to the intake. I had to bend a bracket on the intake manifold that was rubbing against the solenoid, keeping the plate from fully sealing to the manifold
Double check your air inlet tube and clamp

Mike

 

My instructions said to use OE gasket in manifold and new supplied gaskets.
Had to tighten all screws in plate and modify bracket on engine same as
GRABBER.

 

I had to modify bracket as well. instructions didnt specify to use factory seal or not. I think they are tight.but factory spec is small and I dont wanna over tighten. Ill pull the seal see what happens. Thanks.

 

Pulled the factory seal, made the plate flush, made sure all clamps and bolts were tight. Still makes the sound.

 

It runs great, and there are no codes being thrown. Could it be just turbulance?

 

Spray some brake cleaner or starting fluid onto the joints where you think it might be leaking. If the engine rpm changing when the fluid hits the joint then that's where your leak is.