Aircon clicking noise, 1999 B4

[DMN]

Got a strange clicking noise coming from the aircon, on the passengers side, coming from behind/underneath the glovebox. Quite loud on low fan speed. On faster fan speeds, the clicking noise speeds up as well, and fades away.

The noise is only there when the engine is on. Once the engine is off, the noise disappears, even with the aircon going.

Any idea of what the cause could be?

[Guest boostcut]

1, the aircon wont go without the engine running.

2, it will be the fan that makes the noise not aircon

3, remove your glovebox and take the fan out of the box with 3 screws from the bottom.

i garuntee there will be a leaf or something in there.

[subieboy]

 boostcut said:

1, the aircon wont go without the engine running.

2, it will be the fan that makes the noise not aircon

3, remove your glovebox and take the fan out of the box with 3 screws from the bottom.

i garuntee there will be a leaf or something in there.

Yep I concur!

That or twigg or other foreign object

[Guest boostin]

 boostcut said:

1, the aircon wont go without the engine running.

2, it will be the fan that makes the noise not aircon

3, remove your glovebox and take the fan out of the box with 3 screws from the bottom.

i garuntee there will be a leaf or something in there.

The aircon won't go but the fan will, so I doubt it will be something in the fan.

Check that the A/C drain hose and firewall bung are both in place.

[driftrex]

its not an aircon control solenoid of some sort? i dont know much bout subaru aircons, as mine is long gone, but my falcon makes quite a loud clicking noise when aircon is on, which is normal.

[Guest boostin]

 driftrex said:

its not an aircon control solenoid of some sort? i dont know much bout subaru aircons, as mine is long gone, but my falcon makes quite a loud clicking noise when aircon is on, which is normal.

No, they are normally quiet as.

[driftrex]

 boostin']

[quote name='driftrex said:

its not an aircon control solenoid of some sort? i dont know much bout subaru aircons, as mine is long gone, but my falcon makes quite a loud clicking noise when aircon is on, which is normal.

/quote]

No, they are normally quiet as.

not on older falcons lol, like i said though i got no idea on subaru ones as mines been removed for so long.

[Guest boostin]

Yeah I meant Subbies are normally quiet as.

[Guest keltik]

Mine makes a mad loud tick/knock from the A/C pump after track days. Seems to go away if i leave it idling with the air con on full for 5 mins.

Does your clicking noise vary with engine RPM at all?

But I still think its a LOT more likely that youve got a leaf in the blower

[subieboy]

 keltik said:

But I still think its a LOT more likely that youve got a leaf in the blower

I agree

The amount of times I have pulled stuff from the "fan compartment" when there was a sound coming from there...

Do the cheap check first (taking some screws out and looking is cheaper than replacing stuff

[DMN]

 boostin']

[quote name='boostcut said:

1, the aircon wont go without the engine running.

2, it will be the fan that makes the noise not aircon

3, remove your glovebox and take the fan out of the box with 3 screws from the bottom.

i garuntee there will be a leaf or something in there.

/quote]

The aircon won't go but the fan will, so I doubt it will be something in the fan.

Check that the A/C drain hose and firewall bung are both in place.

Cheers for that, will check.

The noise disappears once the engine is off with the fan still going, so doubt its got anything to do with some junk being stuck in there, although wouldn't hurt to check anyway.. Noticed it doesn't depend on the aircon being on when engine's running either. It can be just the fan going - and it kicks in not long after being turned on.

Thanks for all the advice. Will give everything a go, and let you know how it goes.

[Guest boostin]

Can you hear the noise with the bonnet up? It may be something in the radiator fan making the noise.

[DMN]

 boostin said:

Can you hear the noise with the bonnet up? It may be something in the radiator fan making the noise.

Definitely the "glovebox" fan.

Cleaned out the filter, and all the other leaves and crap - no effect

After monkeying around for a little bit longer, it turned out to be a small freakin piece of dry leaf stuck between the fins of the fan, which must have popped out at higher fan speeds, or increased vibration.

All that's left now, is to clean the huge pile of leaves out of the car ;D

Thanks for all the advice once again.

[Guest boostin]

Nice work. ;D