[Cacker]

Hi,

So I've got this intermittent metallic whirring noise that randomly starts getting louder, it's linked to engine revs.

Sounds a bit like when bearings go on a computer fan.

If I hit the aircon button to turn off aircon, the noise stops immediately.

So, are they any belt idlers on the aircon pump belt drive (assuming it's belt driven). Aircon works fine, I asked an Alfa dealer to check the aircon last service in Jan, but they said it doesn't need re pressurizing and they didn't 'hear' the noise I described.

Since January it has slowly gotten louder and louder :/ So much so, passengers now ask what it is.

Secondly, again, bloody intermittently, I hear a clunking noise which I believe is coming from the driver side front wheel area. It honestly sounds like something falls off each time. Imagine a spade being knocked against concrete, a metallic, reverberating clanking sound. It's happened about 4 times in two months and made me thing, "hey, wtf was that !".

The last instance was when braking to a stop, not harshly and the bonnet dipped, compression the suspension, "CLANK", and then rose again.

I've also heard it when doing a sharp left turn out of my estate onto the road, just dips where the two roads join. Again, perhaps causing the suspension to compress/uncompress.

But the noise, it's bloody weird. I wonder if there's a spade caught up in the wheel arch.

Any thoughts ?

 

[Alf M.]

Hi,

I'm sure others will have more experience but on first read:

1) Air con 'on' does put extra load onto the engine (as the advice to to turn off aircon to save fuel would prove), so sounds like a bearing in a pulley or the air con unit.

2) Broken spring? Although.....I had a weird noise the other day that I was convinced was a broken spring but it turned out to be an 8" bit of tree wedged into the subframe near the back wheel that rubbed on something when cornering to the left or going over a bump.

 

[Old Engineer]

I have your first noise. It can be solved immediately by hitting the off button on the A/C. I'm assuming it's one of the flaps vibrating. Mine only does it when the A/C fan is on a higher setting as if the air movement has set up a flutter. If I hit the Off button then the Auto button one after the other it kills the noise. A compressor fault would not respond that quickly.

 

[Cacker]

Interesting. I'll try the Off/Auto switching later today.

Popped into local Ipswich Alfa dealer, Avanti Autos. Initial thoughts are to re-gas the air con unit. He said he had a 159 in not so long ago with the exact same issue and a re-gas solved it.

It's going in this Friday for investigation and hopefully tree or spade removal from the wheel arch.

 

[Old Engineer]

Mine was regassed in January. Still had 94% in so nothing wrong and noise still the same.

 

[Cacker]

Arg. I'll let the garage know, to do some testing before re-gassing. I would have thought that being low on gas the air con unit wouldn't function as well, but I don't have a problem getting icy cold air from the vents when you flip it to Lo.

Secondly, update on the wheel arch spade, this morning I was just 10 metres from my parking spot when I heard what sounded like a part of the car 'grounding'. Funnily enough, the closest noise was dragging a spade along the ground. It was uncanny. it was so loud I had to stop the car, get out and inspect under the car. Nothing. Checked the wheel arch, nothing (although tbh, even at full lock, the low suspension means you can pretty much not see anything behind the tyre). WTF. Set off again, no noise ><. Was expecting something to fall off on the way to work.

I actually aimed for manhole covers, divots etc to see if I could get persuade it to make the noise again, nada. Rocking the front suspension, nothing, ride feels fine as ever.

confused.

 

[alfaholik]

Mine had same issue. Regassed. It's been silent ever since. Nice simple £30 fix

 

[Cacker]

Hope this works, I've shared an MP3 I recorded on my phone, which was affixed around the middle console vent area.

The noise is the metallic, fan-like whirring noise.

At around 30-31 seconds in, I hit the aircon button and you can hear the noise abruptly stop.

rinky dink

 

[Alf M.]

On the 'spade' noise - could it be something hitting/rubbing the wheel rim?
When my noise started I pulled over in a petrol station and could see nothing wrong.
It was only back home, having reversed the car, that I saw the stick. Had it been in that position at the petrol station I'd have definitely seen it.

 

[Cacker]

So a regas has fixed the whirring issue, it was very low. Full inspection of wheels, arches and suspension came up with nothing causing the spade noises and Mario suggested it may be small stone chips getting caught in brake assembly and scraping on disc. Funnily enough our estate driveway is loose stone chips :/

He's happy to fit my suspension kit, whatever I go with, have fitted and recommended eibachs to numerous other cars and for remap is going to ship ECU up to Gus (sp?) of Alfatune in St.Helens.

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