Mac - Intake Noise

[DLee]

I've had the Mac intake for 8 yrs now and pleased with the little bump in performance, looks and sounds good but never had an issue until now...
QUESTION: has anyone experienced a loud humming noise at idle and when getting out of the gas coasting to a stop (almost like a resonating fog horn) ? I've trimmed about a 1/4" off the pipe end to make it flush with the rubber coupler in front of the mfa sensor and messed around with the sensor itself but it's still humming.. Any suggestions? one mechanic thought it was the mfas and another told me it's this little intake box underneath the intake manifold (not sure what that part is called)... Also, I'm new to this forum today so if this doesn't post on the main message board can you tell me how to get it there please? lol - thank you..

 

[ELVATO]

Does it sound almost like a burping sound? Are you having problems idling? Does it make the sound if the RPMs dip below a certain point?

 

[DLee]

Mac - cold air intake noise

ELVATO, thanks for the reply questions... no burping noise or any of the other things you mention.. it's a loud humming noise for several minutes. it used to do it occasionally in colder weather a couple years ago and has gotten worse the last 6 months. when i fire it up now 50% of time, whether engine is cold or hot, it humms.. when you put it in gear and accelarate, it goes away.. then sometimes it will start again when you get off the gas or @ a traffic signal. I've tried to rev it up to get rid of it but no luck.. anyone else have any ideas.. thanks for the feedback.

 

[trdragons44]

is the sound coming from the front end or the "hump"/centerconsole area

 

[86caprirs]

IAC? I know we had the same problems with the duratec v6 contours hooting at an idle when cold. Replaced the IAC and it went away. This is a guess though.

 

[DLee]

the humming noise is coming from under the hood @ the intake/air filter.. think I need to delicately clean the mass flow air sensor?