metallic tapping noise axe engine

[tossman]

I have a confusing issue with my 2006 128kw auto.
Bit over a year ago I notice a tapping/rattling noise from the engine at idle.
I assumed it was the camshaft worn out so figured it would need to be replaced when it got hard to start , Ran rough or the noise got worse.
Well the noise didn't get worse, in fact after giving the engine a degrease and a wash with the hose, The noise actually stopped !Well for a bit anyway.... The moment I started it after its bath I noticed the engine was quiet.
Anyway this was a couple of weeks ago and since then the noise comes and goes, sometimes its there when started, Other times its not, but after idling for a few minutes you can hear it build up and return .
The vehicle has done 280k so I wasn't surprised for it to be the cam... but now im not so sure.
It still goes like a train, I still get over 900km out of a tank.....

Interested to hear if anybody else has had this happen

Mark

[Umai Naa!!]

Does it smell sooty?

A metalic noise is often mistaken for a cracked exhaust manifold at #1 cylinder.

Also worth checking the condition of the water pump, by removing the inspection cover and seeing how much play there is in the gear.

[Sunny43.5]

We had a similar noise with our T5 turned out the bearing in the air con compressor was failing > VW dealer thought it might have been camshaft problem but in the end it was the bearing and it had also caused the mounting bracket to crack and fail , $1600 for repairs as they will only replace the whole compressor , seems dumb to me to have to replace a major part for the sake of a $40 bearing . But from what I have read VW need the old parts back so THEY can recondition them and then sell them back to customers as VW rebuilt parts . This is why VW will charge you extra for a metal component part if you do not give them the old one back , I think this system is wrong very wrong as when you buy the van new you own it lock stock and all parts , if VW want the old ones back they should be paying US for the part not vice versa IMO.

[Umai Naa!!]

You get a decent discount on exchange parts.

[tossman]

how long did you have the noise for in the air con compressor ?
its actually hard to tell where its coming from, its just there !
it doesn't change with air con on or off, I originally thought it may have been the gates couplings so I changed them when It first started.
I think the manifold could have a crack or two. It does smell on start up, no major soot spots that I can see though.

[Umai Naa!!]

In and around the brake master cylinder and on the firewall will be black with soot.

[tossman]

No, its pretty clean. I have read in other posts about "the black soot" so have been fully expecting to see it...
There is a bit of oily black goop down behind the turbo, but I can see its coming from the outlet connection of the compressor, one of the lugs on the connecter has worn away and taken some of the wire clip with it.
One of those alloy forge motorsports couplers will sort that.
I looked into trading the vehicle last week and the used car dude at the dealers reported back that it needs a vacuum pump and its down in the bowls of the engine and will cost a bit over a grand.
Yeh right, he knows what he's talking about. I didn't bother pointing out the dual pump.

[Umai Naa!!]

The vacuum pumps on them are generally ok.

You'll know it's failed when you get a fuel sample that's black.

If anything, it'll be the gasket that's leaking. They're only about $60 or so, and about half hour to replace.

[Sunny43.5]

You get a decent discount on exchange parts.

Not at my local VW dealer they quote the parts price and then tell you there is a refundable amount on top of that they will give you once the old one is returned No mention if it being a discounted price . Or do you mean that the reco parts are discounted ?? as opposed to new parts .

[Umai Naa!!]

They're charging you the outright price, and refunding you the difference when you return the old part.

Which they're entitled to do. Otherwise, if you don't bring the old part back, THEY have to wear the difference, or try and chase you up for it.

[Sunny43.5]

Are you saying that they have a different pricing policy for metallic and non metallic parts . I purchased a new spline recently and there was no mention of "exchange " I cannot remember whether they did it with a clutch kit but I do remember them doing it with some other parts over the last few years a water pump comes to mind in my sons T4. What I am confused about and it goes to some speculation on the net that VW
1/ do not want parts being copied by another party .
2/ Vw do not want faulty common failed parts being shown either
3/ VW ARE reconditioning some parts with bits that they don't sell to the public and then make more money without the high original parts cost . Conspiracy theory people love this stuff .

[Umai Naa!!]

Not all parts are exchange.

Some electronics are, such as radio units and dash clusters. Engines, transmissions, and differentials are. Most water pumps are, and a few other things.

I'd say it's to promote recycling more than anything.

[Adam777]

My water pump went at about 85,000 and the dealers charged me for an exchange part, when i asked to see the old part it got very weird! service manager was giving it "it's already boxed up for collection" i told him i wanted to see the old water pump and eventually after loads of "it's already boxed up for collection" he eventually emerged with it wrapped in a towel only opening it up for quick glances, honestly it was like there was a little baby chick in that towel that was going to immediately escape!

I told him i didn't believe him that VW wanted the old part back, i said "so you're telling me that a company like VW, Audi, Lamborghini, Bugatti, Bentley, Porsche, Seat, Skoda, Scania amongst others want a Fuuurked water pump shipping 12,000 miles back to Germany for reconditioning" He just nodded!

I personally think that the dealers have them reconditioned locally and pass them off to us as new parts with new parts prices.

Forgot to mention that upon dropping my van off he suggested to me they "may as well do the cam belt while it was in" good luck with that one! they scratched an otherwise unmarked van and told me it was "already on there", when i went to pick it up it was still on the ramps and service guy said he was "just about to ring me" and "what oil did i want putting in the van" tried charging $300+ for oil on top of the $600 and something quoted for the initial job doing, so i rode 17 k's back home on my mountain bike and returned with 10 litres of my own stuff and then i never got any back, i asked where the rest was and that there should be over 2.5 litres left and he scuttled off into the workshop again and returned with a thimble full left in the bottom of a 10 litre drum! My head hurt!

Main dealers for you!

[Umai Naa!!]

No, they definitely go back to Germany.

They reuse the housings again.

[Sunny43.5]

If what you say is correct Umai why don't the spare parts people offer them as an alternative when you go in to buy a part . its never happened or been offered to me . Adam did they fit a new pump or a reco one .