Hey all,
I'm wondering if anyone else has encountered a whistling from the area around the intake on a 4 cylinder Mazda 6. To be more specific, the throttle body. This Mazda has a 116000 miles, hasn't been over heated or anything like that. About a month ago it developed a whistle at idle. The whistle has become worse and can now be heard while driving. Problem is the sound can't be located. Haven't taken anything apart, but have tried spraying carb cleaner at as many vacuum ports as could be seen. No change in idle was detected.
I'm pretty sure it isn't a belt, or accessory because there are none in the area the noise is coming from. Other symptoms are rough idle, and the CEL is on. I know...check the codes, which I will, but I doubt there will be a code telling me where the vacuum leak is located.

Thanks for any help.

 

sorry to hear about your issue.

Is the sound a contant pitch or does it change with the rpms?

 

Thanks,
It stays about the same pitch, but does get louder as the RPM's
increase. This ia a very strange problem.
The intake appears to be made of some type of plastic, am I correct in assuming this?

 

so I am not sure about the plastic, i would assume so-it couldnt really be made of anything else.

If it changes with the rpms then it is most likely something which is run from of by the belt. i had an issue with my last car, a monte carlo and there was a buzzing which matched the revs, I thought it was the altinator, however it turned out to be the powersteering system. Their was a crack in my steering rack which drained the pump and therefore it was operating without fluid. For you, I would check all your fluids as a start. see if anything is low which may pinpoint the problem (if its mechanical). if you think it is the airbox, maybe you have a leak somewhere on it so try soapy water around it.