Timing chains AGAIN!!!

[nihc]

There is a recent Audi technical bulletin which I have read that states that no dealership should change chains or tensioners for the V8 4.2 rattle problem on warranty as it's not a problem - unless of course they rattle all of the time
I think the dealers have been making a mint from this and Audi have realised and put a stop to it. It would be interesting if anyone can now get the "problem" fixed.

[else]

Thats interesting, I could have told Audi that, mine had the chains and tensioners changed which made no difference at all.

The dealer has promised to fix the fault but Audi need time to investigate.
Rang the dealer last week and the next item under suspicion is an oil control valve which is being changed on one of the other S4s that they have in. If that cures it the same fix will be applied to mine and the others that are waiting.

Andy

[nidfix]

There is a recent Audi technical bulletin which I have read that states that no dealership should change chains or tensioners for the V8 4.2 rattle problem on warranty as it's not a problem - unless of course they rattle all of the time
I think the dealers have been making a mint from this and Audi have realised and put a stop to it. It would be interesting if anyone can now get the "problem" fixed.

On one of the tsb I have it also says that the initial rattle is a normal noise and they should not change anything. There is another tsb for the whine (while the engine is cold) which describes belt and tensioner replacement, but it is clearly not about the camchain.
These are two different issues

[archboldm]

Finally had the gas conversion done a few weeks ago & I can report there are no problems so far.Only thing I can say against it really is the tank is too small & it takes ages to fill,much slower than petrol.Other than that,I think it was money well spent,When I work out how to load pictures on here,I will post photo's of the conversion.

[tweek]

Would interested to know your running costs on LPG compared to petrol? Out of curiosity, is there a separate oil tank in the system. A friend had a volvo with LPG conversion and suffered a burnt valve with a subsequent hole in the wallet because it was it ran out of oil.

[archboldm]

Averaged about 22mpg on petrol,now averages about 17-18mpg.but at 52p a litre,I can live with the small drop.Also,no noticable difference in performance at all,other than a small throttle lag for about a minute after it switches from petrol to gas in the morning.(it starts up on petrol,then swiches to gas after about 2 minutes from cold).No seperate oil tank & I have had no problem with increased oil consumption,& I do check it regularly,(at least twice a week as I do a lot of miles )

[tweek]

52p a litre, that is the same as geting 40mpg on petrol....How much did the conversion cost? assume the tank is in the spare wheel well and who did it for you.

[archboldm]

The conversion was £2500 all in & took 4 days,but You do get a courtesy car.It was carried out by CLS dualfuel,They seem very knowledgable & when I took my car in,he said they were doing about 60 conversions a week,I had to wait 9 weeks to get mine done.As for the cost per mile,I'm doing better than my son in his 1.4 fiesta !!! Oh,& just as a little bonus,My car tax has gone down by £10,isn't the government great !!! knocking all that money off for having a green car,!!! & in london,NO congestion charge.

[SimonC]

Would interested to know your running costs on LPG compared to petrol? Out of curiosity, is there a separate oil tank in the system. A friend had a volvo with LPG conversion and suffered a burnt valve with a subsequent hole in the wallet because it was it ran out of oil.

Burnt exhaust valves are a common LPG issue due to the slower burn rate of LPG (ie the waste gases are much hotter as they're being pushed into the exhaust manifold). This can be mitigated slightly by taking advantage of the higher relative octane of LPG and advancing the ignition timing.

[archboldm]

I went through all of these issues with the company that fitted the kit & they seemed to know of the valve burn problems of earlier units.To this end,a seperate ECU is fitted with mapping to negate this problem.I suppose only time will tell whether this is the case,but with a 2 year warranty & assurances from warranty direct that they will continue to cover my car with the gas conversion without exclusions to the policy,I feel I have every base covered !! As I said in a previous reply,I will post some pics if someone tells me how to do it ???

[Vorsprung_Durch_Technik]

I hate to revive this once again, but I want to run something past you guys.....

I have had this problem (or characteristic as Audi seem to call it) since I bought my S4 over a year ago. I have found an oil which ar regular changes (about 4K) seems to dramatically reduce the problem, (Fuchs Silkolene ester based 5W 40 - thanks to Guy at Opie Oils for advice). But occasionally it rattles extremely badly at startup, then others not at all. The car has an approved warranty on it, but as nothig is actually broken this is not somethign that the warranty will cover, especially given the fact that from what I can gather full chain and tensioner changes do not solve the problem.

Looknig for advice here really, as to whether this is something which I should be taking further, or something that just is. If all you guys with problems would be interested I would be prepared to try to get somewhere with this if I could get your car and owner details... Maybe a group complaint would be enough to make some progress, I dont know. Just an idea.

Im beginning to consider getting rid of the S4 to be honest, as I realy hate the noise. I love the car, and its immaculate, but I think to myself how in the world can this be NORMAL!!!??

Comments welcome..

[B6S4John]

from what I can gather, full chain and tensioner changes do not solve the problem.

They did with mine, it was done under warranty at 11,000 miles in 2005. The noise was very bad before, and none existent after. The car has still only done 29,000 but has never had the noise since.

[Vorsprung_Durch_Technik]

hmm, thanks for that John, from reading I had assumed the chain and tensioner change made little difference. thanks mate I think a visit to Edinburgh Audi is required!!

[xyber]

Have any of you tried Liqui-moly CeraTec oil additive? It was developed with VAG specifically for chain driven engines. I used it on my Golf VR6, which is also chain driven and suffers from the same worrying noises in the cold and sometimes on start up and has a generally noisy engine. It basically leaves a coating on everything it touchs and lasts for 30k miles. Vince at Steath Racing recommended it to me and it did what it said on the tin and quietend the whole engine noticably. May be worth trying, its about £25 but often pops up on ebay for £15

Their gearbox additive is also as good as Slick50 MT-90 if you fancy that aswell

[MICALEE]

Hopefully, Im on the right thread here. Mine makes a whining noise on start up - for about 5 mins in morning until warm, and recently anytime now when the engine hasnt been used for a while.

I have recorded the sound here:

http://s4.photobucket.com/albums/y105/j ... V01448.flv

Hopefully you can here what I am on about. Towards the end of the clip, the camera points to where the noise is coming from (right hand side of the engine)

Audi told me it was due to the components being under extra load until all the oil had circulated and given them some lubricant. He added it was a characteristic of the S4, did no harm but couldnt be fixed.

Is there a way of improving this? Different oil? or can there be something done under warranty? I would say its quite embarrasing first thing every morning - I bet the neighbour thinks I have a bit of a dog as its only the morning when he hears it!