whistle from air intake?

I have a 97 grand prix 3.8 vin k. I installed an air intake chrome tube with a k and n filter to replace the stock. Since the switch i where a whistling sound. took the air filter off for a brief amount of time and still does it. It sounds like its coming from where the filter and the tube connects. I made sure the connection was tight with the rubber fitting. any help would be great.

Doe's it throw a DTC P0171 - Lean code

You might beable to use a little silicone sealent for install.

no codes are being thrown.... just the whistle noise.

Check the large vacuum line coming off the front of the throttle body.

what does the vacuum look like and what am i suppose to look for exactly. i looked at the t line and didn't see any sign of a hole ect.

does this intake have a back-fire relief valve on it? The can be cruddy and if a intake pop occurs it may not seat properly. They are usually opposite end of the intake.