A few months back I had my power steering belt snap and shred in the driveway, it wrapped around the pulleys and whatnot but I got it sorted.

In the process I had to remove the AC belt of course, ever since whenever I turn the Aircon on it makes a very small clunk and then kicks in. The clunk is only really noticeable to me as the driver but it feels like I have just gone over a small pothole or driven over one of them little square things in the middle of the road that reflect the light at night. So it is by no means a massive issue, and it only does it the first time I turn the aircon on after being off overnight or for a few days, after its been on recently I can turn it on/off all day and nothing happens.

I assume its only the belt being on too tight or loose (I did the best I could to tension it correctly to the right amount of play according to the service manual), however I dont want to loosen it and then find out the hard way I should have tightened it or vice versa.

Cheers.

My car does the same thing, mechanic told me he thought it may have too much gas which liquifies causing too much compression on first start when its cold.

Kinda rules that out though if all you did is replace a belt and it didn't do it before hand.

Does it do it if you let the car warm up for a few minutes on first start for the day before you turn the a/c on?

It only does it in mine when its dead cold.

My car does the same thing, mechanic told me he thought it may have too much gas which liquifies causing too much compression on first start when its cold.


Hopefully thats all it is. It doesnt cause an issue, just good to know its not only me.


Kinda rules that out though if all you did is replace a belt and it didn't do it before hand.


Yeah but the tighter belt could equal more/less resistance, it could have done it before just less noticeable as the belt may have been tighter/looser.


Does it do it if you let the car warm up for a few minutes on first start for the day before you turn the a/c on?

It only does it in mine when its dead cold.

I can drive all day long without the aircon, then switch it on and sure enough....clunk.....cold air.

I wish I'd never noticed it as its only a tiny noise but now I listen for it everytime :P

Mine does it too. It's the magnetic clutch on the a/c compressor kicking in. Mine can give a high pitched metal on metal squeal if I turn it on in really hot weather. The initial startup of the compressor meets the most resistance, thats why. If it bothers you just turn the air on before you start the engine. Compressor starts up with the engine, no noise.

hmmm when i got my air con regassed, after my engine conversion, the system was suspected to be overcharged.
or too much gas so to speak, i dont remember hearing any clunks, but the air con was cutting in and out. i figured a safety feature disabled the air con as the pressure would be too high. after removing some gas, it began to work normally again. have you noticed any similar symptoms, as this would indicate an overcharge

mine does it right after starting sometimes, had it checked and was told it was just the clutch on the compressor engaging or something as they're magnetic, my gf's tl gives a tiny squeak when it engages sometimes.

mine does the same thing

Mine does too. Clunk can be load sometimes

Hmmm... along with the "clunk," does the headlight dim very slightly (but comes back to normal brightness in less than a second) when the compressor kicks in? Mine is TW magna.

My baby does it too, but i dint know what it was so i took it to have it looked at & they told me not to worry about it. They explained that it was just the airconditioner kicking in eventhough sometimes it almost stops my car when i 1st switch it on, but it only happens sometimes. :)

Later :)

I have the clunk intermittently, but only ever when it is cold (the engine).

Also, strangly, the snowflake symbol sometimes flashes and the air seems to not be working properly.
This usually happens after a carwash or when there is very heavy rain. The fix as far as I've determined, is to pull over, turn the car off and turn it back on again.

Has this happened to anyone?

Hmmm... along with the "clunk," does the headlight dim very slightly (but comes back to normal brightness in less than a second) when the compressor kicks in? Mine is TW magna.

exact same thing mine does,i didn't do it when i brought it though lol

I have the clunk intermittently, but only ever when it is cold (the engine).

Also, strangly, the snowflake symbol sometimes flashes and the air seems to not be working properly.
This usually happens after a carwash or when there is very heavy rain. The fix as far as I've determined, is to pull over, turn the car off and turn it back on again.

Has this happened to anyone?
Never experienced this. In most cars if the A/C light flashes it usually means there's something wrong with the A/C system. In 3rd Gens with climate control i guess the same would apply but you would substitute the A/C light for the snowflake symbol.

I think the "snowflake" being referred to is to when its icy conditions. But obviously, the sensor for sensing ice might be faulty. It would make sense though because icy conditions are cold and humid, hence it is probably sensing extreme humidity from carwash and heavy rain, but not the coldness of the air..... my 3 cents.

think the "snowflake" being referred to is to when its icy conditions. But obviously, the sensor for sensing ice might be faulty. It would make sense though because icy conditions are cold and humid, hence it is probably sensing extreme humidity from carwash and heavy rain, but not the coldness of the air..... my 3 cents.

Cheers for the thought, and the car can detect icy conditions as the system will beep at me if it gets below zero.

But the snowflake symbol im describing, is on the screen in the climate control. It comes on when the aircon compressor is working. Thanks also to Mohit. I had a search of the manual and the symbol flashing indicates a compressor malfunction. What I think is happening is the system just sometimes doesn't engage the clutch properly (?) This maybe because I rarely use it.

Cheers for the thought, and the car can detect icy conditions as the system will beep at me if it gets below zero.

But the snowflake symbol im describing, is on the screen in the climate control. It comes on when the aircon compressor is working. Thanks also to Mohit. I had a search of the manual and the symbol flashing indicates a compressor malfunction. What I think is happening is the system just sometimes doesn't engage the clutch properly (?) This maybe because I rarely use it.

WOW... The Veradas are really high tech..(I am NOT being sarcastic) I am still discovering new things with mine also, just being standard VRX. I just discovered the other day (off topic) Time delay headlamps, I am finding it really usefull since i discovered that. Worse thing is, mitsu guys never made a big HOO HAA out of this feature and only a 2 liner in the manual..

I experience the same clunk in my TS as well.

Air-con belt replaced 12 months ago, all went well, then the clunk began 3-4 months back. If the air-con is left on "Economy" mode, as the compressor turns on and off, the clunk continues with each cycle.

I've found (being a manual car) that I can minimise the "shock" of the air-con kicking in, if I drop the revs to idle speed (ie. just press the clutch in) and then turn the air-con on.

If I am travelling at highway speeds, my air-con will also squeal for about 1-2sec when turned on initially.

Cheers for the thought, and the car can detect icy conditions as the system will beep at me if it gets below zero.

Is that just a verada climate control thing? I remember last winter going for a drive up the range and the outside display being at around 3 degrees, going down a hill and it hitting 0 or -2 degrees and no beep.

Is that just a verada climate control thing? I remember last winter going for a drive up the range and the outside display being at around 3 degrees, going down a hill and it hitting 0 or -2 degrees and no beep.
It's a 3rd Gen climate control thing, beeps at you when the outside temp gets below a certain temp.

when it hits 0 mate then she beeps at ya :) happens fairly often here in Tas :).

good to see im not the only one with this problem, i am a qualified a/c technician, and in 11 years of fixing cars ive never come across this noise

if the system were overgassed then the compressor would moan and cut out prematurely without getting cold
a compressor failure either results in seizure and a snaped belt,a horrific noise when engaged, or not pumping and an over tightened belt causes a bearing noise when the system is off.

when i get time im gonna rip off my compressor clutch and hub as i suspect that it may be a common fault that causes a hairline crack in the hub or its just a matter of machining the faces/replacing the clutch and hub

will keep you updated

"If I am travelling at highway speeds, my air-con will also squeal for about 1-2sec when turned on initially."

Tighten the belt!

good to see im not the only one with this problem, i am a qualified a/c technician, and in 11 years of fixing cars ive never come across this noise

if the system were overgassed then the compressor would moan and cut out prematurely without getting cold
a compressor failure either results in seizure and a snaped belt,a horrific noise when engaged, or not pumping and an over tightened belt causes a bearing noise when the system is off.

when i get time im gonna rip off my compressor clutch and hub as i suspect that it may be a common fault that causes a hairline crack in the hub or its just a matter of machining the faces/replacing the clutch and hub

will keep you updated


Check the clearance between the drive and driven plates and compare it to specs.
I have a theory that the clunk is caused by excessive clearance due to normal wear on the plates as the electromagnetic clutch cuts in and out millions of times over its life.