R33 Gtst - AC noises every ~30 secs

[HCD_Velcra]

R33 Gtst - AC noises every ~30 secs

Hello guys

When I turn the AC on, every ~30 seconds I can hear a sound from the outside, Im not sure how its exactly like, but Id describe it with "fizzle" combined with a short engine stuttering like you know it from broken coils.
Id also say, the intensity depends on the speed you drive; it doesnt seem to appear while standing with the and engines obviously running on the common 700/750 rpms

We recently did the whole timing belt change, could this have something to do with it?


Thanks a lot

[89CAL]

If its on the 'outside' then it can only really be the compressor or a leaking line. Perhaps something wrong with the A/C Fan on the condensor but doesn't sound consistant with what you have described.

Sounds like A/C Compressor if it changes with RPM. Could be an issue with a bearing of the clutch, or might be a belt issue also

[HCD_Velcra]

Ok ok so what would be my next step? Tighten the belt wouldnt change a change would it? I was thinking about a leak too therefor I stopped in a bus lot, but I have not heard anything. 

[89CAL]

Does the noise go away immediately when you turn the A/C off? If so it shouldnt be leaking gas, more likely belt or compressor clutch

[HCD_Velcra]

Yeye, theres nothing whilst driving without the AC. How could I find out about that clutch?

 

Thanks so far

[KiwiRS4T]

Stick you head under the bonnet and get someone else to turn the aircond on and off while you try to pin point the noise.

 

[HCD_Velcra]

Like said, not working without driving - I do believe its worst when 4th gear and about 3500rpms - its almost like an aftermarket bov man.... What could that cause other than a leak which it is obviously not the case

[89CAL]

Is it absoloutly the AC? It behaves no differently free reving or driving really so you should be able to hear it with the car stationary

[HCD_Velcra]

Hm, what I can say for sure, it only appears when I turn AC on; with the right rpms it comes straight with the button pressing and then like I described - every 25/30 secs.

I had the feeling, that it almost sounds like something pulling hard, but thats just one of those "maybe possibilities thoughts if the mainthought is wrong" ^^ And the main thinking is that air pop sound. 

I dont know exactly when it started, but we changed the whole timing belt stuff 3 weeks ago and everything was fine before - but would that have something to do with this issue?

[89CAL]

Can you get a video of it to show us?

[HCD_Velcra]

^^ Like said, 3rd 4th gear hard to film and understand anything; we tried to get the sound but you mostly get wind screaming obviously; Ill give it another try in the weekend so you might check out for yourself

[tridentt150v]

I have this issue as well....its like a small sneeze.  I have it on my Gtst AND my ford courier both.  Had both vehicles to the aircon specialist here and he laughed but after taking the courier for a drive came back scratching his head.  All gas pressures are fine, the condenser and all other parts are fine, everything tested perfect.  He said drive it till it fails

Well I have been driving both vehicles now for over 2 years and except for the sneeze...nothing...everything is working perfectly.

More worried for the courier cos its a single belt, but so far so good.

I am not sure if the engine stutters or not, I sometimes thing it does, and other times think it doesn't.  I think its got something to do with the condenser cutting in and out and loading the engine - as opposed to a misfire.

[HCD_Velcra]

Well ye I could live with it IF it would be normal like everybody says - but as I mentioned it just came up after timing belt stuff and I dont wanna get used to something that is so obviously "wrong". I tried to record it but its hard cause of the wind or murphys law - everytime we try to record - nothing. Trying just to know - major sound ^^

 

Try this one pls, its one of the quieter appearances but you can hear it in the end.

its an opus file - just use VLC

 

2017-07-23-AUDIO-00007494 (1).opus

[tridentt150v]

All I can hear in that file is the motor....no fizzle or sneeze sorry.  Used headphones and even swapped them around left to right but nothing.

[HCD_Velcra]

What?! I seriously wonder....

That sound a moment before the end

[tridentt150v]

Maybe I'm not getting the whole file...only goes for 3 seconds.  I'll try downloading and see.

 

Edit....nope same, no sound other than the motor and only for 3 seconds.

[HCD_Velcra]

Yes 3 secs almost in the end - Ill edit it and make the sound louder