Buzzing/whistling when accelerating

[chewy666]

Hi, I have a strange buzzing/whistling noise I can here inside the car when accelerating hard. Sounds like it's coming from the engine area and is most noticeable when around or above 5K RPM. As soon as I back off (i.e. to change gear) it disappears, but then immediately re-appears as I open the throttle again. The car is a cupped 54 plate 182 FF, 32K miles.
Also, have no idea about mechanicals in cars, so keep any explanations simple .

Any ideas??

 

[chewy666]

Is it likely to be the Aux belt? I've read about that making a strange noise when accelerating... It will get done at it's next service (as it will be the 36K service), but is it likely to explode if I wait?

 

[Track'd]

It could be that as i'm getting a similar noise. I've just heard my 36k service but was told it was just a visual check on the belt and it would be done at 72k. I'm now hopefully getting it done in next few weeks... i've been told to just get the belt done too, not the whole kit as it's normally just the belt to go anyway.

hope it is this though

 

[andyroo]

I have this, I'm gonna take a peek at the weekend, I'm thinking either cold air feeds into the airbox being loose or squashed or the cat needs adjusting (it hangs down a little and I caught it on a speed bump recently) so I'll let you know what I find! Either problem will have air moving over an uneven surface and escaping causing the noise.

Does yours almost sound like there is a peice of paper flapping about in the wind?

FYI I have an 05 182 ff with cup packs

 

[chewy666]

No - mind sounds more like a buzzing. I initially thought it might be the engine cover rattling; but I don't see how it would stop rattling when I eased off the gas. The revs are still the same, so would still "rattle" the engine cover...?

 

[andyroo]

If its affected by easing off the gas, then airflow is probably the cause somewhere... as you step on it, the throttle body opens and lets more air through, increasing air sucked in and pushed out, which is then disturbing whatever is making the noise! It could also be that as you accelerate hard, the engine moves back as it is under load and then comes into contact without whatever it is vibrating?

 

[chewy666]

You make a fair point! Perhaps I'll have a quick look at the engine-cover anyway. Please post if you manage to solve the problem this w/end - it's not a major issue for me, so as long as it isn't damaging anything I will wait until my service to get it looked at (unless it's so quick and easy to fix I can do it myself )

 

[andyroo]

Checked the cat, cant see anything obvious, no smells/noises out of the ordinary. Checked the airbox, everything seems plugged in ok and the pipes arent crushed. Might possibly be that noise suppression valve whatever its called. Is there supposed to be a pipe connected onto both sides of it because mine only has a pipe going in then what looks like a plastic sleeve to connect a pipe onto on the other side of the valve.