Volkswagen Mark IV Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
319 Posts
sadly as far as i know this is a bad sign.

is the sound coming from in the car or outside(ie the engine bay) if its from the engine bay i think it may be a fan thats knacked. there was a thread on here about it quite recently if i remember.

hope you get it sorted and sorry i cant be more help mate
 

·
Registered
Joined
·
1,903 Posts
When you hear this is it like someone is thumping on the front of the car??

If so then it sounds like the vacum pump thing below your drivers side headlight which has something to do with the power steering.

When mine started rumbling they changed the power steering pump and it has been ok sinse.
 

·
Registered
Joined
·
318 Posts
If it`s only noisey with the aircon switched on your aircon compressor drive pulley may be loose.It`s held on by a small nut and they do have a habit of working loose.The noise only appears when the aircon is on because the centre of the pulley (the loose part) is not turning when the aircon is switched off and the magnetic drive is in free wheel mode.If I were you i`d be heading straight to my garage to get it checked and tightened before too much damage is done as a new aircon compressor costs in the region of ?350 - ?400.

[:|]
 

·
Registered
Joined
·
251 Posts
I've the exact same thing. With air con on and engine at idle, very
noticable rattle from engine bay area. It has alwys done this (5 years
old now!) In the meantime the pump has been replaced for a different
problem, and rattle remains. VW couldn't find anything wrong! I believe
it is just something else slightly loose and when the aircon is on, due
to the slighly more load on the engine is alows whatever it is rattling
to do its ting. Increase the revs and it goes away.!
 

·
Registered
Joined
·
7,465 Posts
^^ RaT has it done it for 5 yrs? ie from new??

As posted in other threads mine too has the 'noise' - I'm going to change the drivebelt (?26 inc VAT from the dealership) at the weekend and see if it cures the problem. Mine seems to be more pronounced when the car (and the weather) is warm, and can be heard ever so slightly when the aircon is OFF too, which makes me think it 'could' be the belt..

I've checked my compressor pulley bolt, belt tensioner and fans and all are fine.. Its all a bit strange, but I can't leave it alone as it don't sound that cool does it??! hehe
cheers, Pat
 

·
Registered
Joined
·
7,465 Posts
Let us know how it goes Matt, I'd be very interested to know the source of the noise. I'm going to get the new drivebelt this aft and fit it if I've got time so I'll report back.

thanks, Pat

ps wonder if it's only people that have 'at' in their name that this problem affects?? Matt, RaT, Pat... hehe
 

·
Registered
Joined
·
7,465 Posts
It might not be...

'Unfortunately, VW dealers do not like to work on air conditioning systems and will often sub contract out any work to a local air conditioning specialist. A consequence of this approach is that the only likely course of action that a dealer will recommend is to replace the complete pump even if this is not actually the most cost effective solution to the problem. A replacement pump assembly will cost in the order of ?600 from a VW dealer. Even a new clutch assembly will cost around ?200 from a dealer, and unfortunately it is not currently possible to purchase any major components for the Sanden pumps from any other source.'

useful words from RallyChris's site
http://www.golfmk4.co.uk/air_conditioning_pump.htm

maybe take it to an aircon specialist or independent VW garage for a second opinion?
 

·
Registered
Joined
·
7,465 Posts
Quick update for you:-

I fitted the new drivebelt earlier on today and as yet (fingers crossed) NO MORE RATTLE!

woohoo am I a happy man. I'll run it for a few days and keep checking but it seems to have worked. I compared both belts old and new, the old one had stretched quite a bit compared with the new one.

5 mins of a job to fit too, can't be bad!
 

·
Registered
Joined
·
7,465 Posts
It was just shy of ?26 for the belt, from the dealers. I did mine in less than 5 mins without going in from the wheelarch (I have quite small arms and hands which no doubt helped!). Just use a 15mm spanner in a clockwise motion on the tensioner, insert a drill bit into the 2 holes that you will align when moving the tensioner, and the belt simply comes off the pulleys.

I still have no noise /touch wood/
Good luck mate
 

·
Registered
Joined
·
32 Posts
Mine is in at the specialist and has been since Monday morning they say it is a faulty tensioner and damper and also the belt that was on was not a VW belt. so he is going to replace them and the engine mount bolts aswell as they are stretched. Total cost ?305.
 
1 - 17 of 17 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top