Hi guys,

 

 

My car has been making an odd noise for a little while now.

The screech happens when you press the AC button even with the engine off. Does anything AC related besides the fan on the condenser turn on without the engine being on? Obviously the compressor is belt driven. 

 

Then you can hear the clicks after turning the car on, sometimes its worse than this. Think that may be the compressor pulley bearings and/or compressor clutch making the clicking noise?

 

The rattle you hear after the clicking stops (aside from the normal engine rattle) is the tensioner, which is fine, I'm doing that soon, but want to sort this lot out too while I'm at it.

 

After sitting all night in the 'cold':

 

 

And again after sitting for 8 hours in the warm multi-storey, slightly different/shorter squeal this time, and minimal/no clicking after starting:

Anyone have any ideas on this one? I have trawled the net and found no recordings like this! 

Squealing happens if you turn the engine on straight away too, but I did it like this so you could hear it better. 

Many thanks!

Edited 14 September, 20169 yr by acme15

offtopic: do you have mk2 AC controls in a mk1 octavia? Or is this some sort of strange crossover? It's really confusing me.

 

On topic, I don't know the answer but I'd start by removing the AC electro clutch as this is fairly easy. Then see if the noise persists. Maybe it's all rusted up inside that mechanism.

I didn't think the fans fired up without the engine on but if they are doing I would start with those and disconnect them, see if the noise goes.

AC controls are normal ones, just have different knobs.

 

I'll start by disconnecting the fan and see what difference that makes. What actually powers on when the AC button is pressed but the engine isn't on? I think the fan does but will double check.

 

What do you think the clicking noise could be? It did it for ages this morning, and louder than in the video, was a little concerning to be honest!

Edited 15 September, 20169 yr by acme15

Stick your head under the bonnet, the pumps and fans are apart in the engine bay so you will be able to pin point the location of the noise with your head under there.

 

If you can't then take it to a garage.

Will do when I get a chance (tomorrow! )

Took this video when leaving work today, this is how bad the clicking is sometimes. Curiously, no whine this time... 

OK so the clicking noise in the above video seems to happen without AC turned on as well, but gets worse when the AC is turned on.

Its coming from the 'aux area' somewhere. Someone suggested that it could be the alternator, and the noise gets worse when the AC is turned on as more strain is put on everything.

Now I know the tensioner is worn out and rattles but that is a seperate noise so I think that rules it out. I'm thinking it could be the alternator pulley/freewheel clutch/bearing?

The car didn't make the 'other' noise this morning so I haven't had any luck physically locating that one just yet! :(

Edited 16 September, 20169 yr by acme15

Changed the aux belt and tensioner, the rattling has gone, haven't heard the clicking again yet either... Looks good so far!

 

Old aux belt was in a sorry state with chunks of the ribs missing!!

When was that last changed

Chances are the alternator pulley is knackered and has killed the tensioner. Keep an eye on it.

What am I keeping an eye out for?

If the pulley is an easy job I might just do it anyway to be on the safe side. 

 

e; looks like an easy job, belt off again, and basically swap the pulley from the top... Will order one now...

 

e2; Ahh damnit, which pulley do I need? :(

 

This one? http://www.ebay.co.uk/itm/NEW-SKODA-OCTAVIA-1-9-SDI-TDI-ALTERNATOR-FREE-WHEEL-CLUTCH-PULLEY-1998-2010-/321658867228?hash=item4ae45cce1c:g:viAAAOSwqu9U0LIR

Edited 19 September, 20169 yr by acme15

What am I keeping an eye out for?

If the pulley is an easy job I might just do it anyway to be on the safe side. 

 

e; looks like an easy job, belt off again, and basically swap the pulley from the top... Will order one now...

 

e2; Ahh damnit, which pulley do I need? :(

 

This one? http://www.ebay.co.uk/itm/NEW-SKODA-OCTAVIA-1-9-SDI-TDI-ALTERNATOR-FREE-WHEEL-CLUTCH-PULLEY-1998-2010-/321658867228?hash=item4ae45cce1c:g:viAAAOSwqu9U0LIR

 

 

It's and alternator out job and you need the correct tool.  If you pull the plastic cap off the end of the pulley you can read the part number (not a VAG part no though), it's probably made by INA.

 

The alternator will have to come out the top and you will need to undo the power steering pump from the bracket to get it out.

Thanks for the advice. 

I'll try this way first:

 

http://forums.tdiclub.com/showthread.php?t=234251

 

Then take it out if I need to.

 

Also to add, the weird squealing noise hasn't happened again yet either, it used to do it every day without fail. The clicking noise has stopped too as mentioned, and the tensioner rattling has as well. 

There is visible vibration on the lower part of the new tensioner, but it looks fairly normal? It certainly isn't rattling around like the old one did. I'm guessing it won't ever be totally still due to how it works.

Just trying to figure out if there is actually anything up with the alternator pulley, but I guess the only way to be sure is to check properly.

 

When was that last changed 

 

At a guess... Around 60K ago, maybe more. Some of the service history is in (I think) Hungarian. 

Edited 19 September, 20169 yr by acme15

The bolt holding the pulley on is very very very very very tight. Best thing is to use is an impact gun.

I had the alternator strapped to a bench and had to use a breaker bar with a 6 ft scaffold pole over it and all my body weight to loosen it. This was after soaking it overnight in proper Penetrating oil.

Edited 20 September, 20169 yr by trundlenut

Well I've done nearly 1000 miles since changing it now and it seems to be fine still. Hopefully it stays that way!