jmclellan

Hey everyone,

2 weeks ago I bought a used 2004 S4 with around 69thou kms on it. Beautiful condition, Audi certified, all the major wear parts (clutch, tires, brakes, rotors) replaced and the full Audi inspection was done. I went through the vehicle with a fine tooth comb before I bought it and it was immaculate. So my vehicle paranoia kicked in the other day when I started it for the first time in the morning after it sat in my parking garage for the night.
Upon cranking the engine, for the first 10 or so revolutions there seems to be a metal on metal "shudder or clanking" sound that happens right when the engine fires up but immediately goes away. It will not happen again unless the car is left for over 12 hours in the cold parking garage. I can even fire it up, and shut it down immediately and i can not duplicate the noise.
From my basic mechanical knowledge I can tell everyone that its not the starter, and the sound sounds more like taking a piece of sheet metal and tapping it against another metal object. It makes no other noise throughout the entire rev band, just that initial "cold startup" noise.
So i scoured the internet and found only 1 site that made mention of the phenomenon..... v8esfo.com
The author addresses this noise as a "subtle nuance" of the 4.2 engine, and that is literally the only resource I can find on the matter. I contacted Audi care and they had no bulletins or recalls to tell me about but (of course) suggested I take it to the dealer.

My problem with the dealer is... if I take it to them, they will need to park it inside or somewhere cool for the entire night, and when they start it in the morning, they will only get 1 shot at identifying the noise, because even if they shut it down and try again, the thing wont make the noise. So that means I give up the car for 2 days and they tell me nothing is wrong! haha lame...

My question to all you 4.2 owners out there (especially the B6 2004 people) is HAS ANYONE EVER HAD THIS HAPPEN TO THEM? Should I stop being paranoid and chill? If this has happened to you, had you gotten any answers at all? Any repair advice? Any damage this may be from or (worse) may be causing?

Thanks in advance for any ideas guys...

J

zebinheimer

from my experience with most cars, and on the 5v's (i own a 2.8l 5v not a 4.2 i know.) there is simply no oil upon startup in the heads (very little at best) so that noise would be the valves ticking loudly until the oil reaches them and it goes away, as with the nature of oil's viscosity, it would take a long time (say 24 hours lol) for it to "dry out" and have all the oil sink back down into the pan. my car does this, several other cars i know do this. I would say it is nothing to worry about IMO. hope that helps

jmclellan

That seems to be the general consensus in the Audi world... I think I am being a little too paranoid about my new toy.. I will update if it gets worse, or something terrible happens (knock on wood) ha!

Thanks zebinheimer

ricoblanco

I know it doesn't mention the //S4, but your engine is on there. No worrys! :-)

<img src="http://i255.photobucket.com/albums/hh156/ricoblanco/Rattle1.jpg">

<img src="http://i255.photobucket.com/albums/hh156/ricoblanco/Rattle2.jpg">

zebinheimer

valves, cam tensioners, meh close enough same shiz haha

jmclellan

You guys are awesome... appreciate it very much..

jmclellan

sweet thanks pal

mikebessxxx

Re: I have exactly the same thing on my s8

phatbooker

after much searching I have found many many people with the same issue. Read all the bullitens and think its BULL**** ! I own a german luxury sedan that sounds like a **** box on start up. Its great when your leaving somewhere quiet and you have to fire up something that sounds like an antique tractor. very embarassing. I think audi needs to adress this issue somehow.

dleasman

I had this same sound on my B6 S4 4.2 on cold starts. The solution was for them to flash new firmware into the ecu.

The problem was caused by a flap that opens and closes to align somewhere in the exhaust. They gave me a page with all the details of the cause and fix.

Basically, the fix was that after a cold start, it waits until the first time the car hits 20mph to actuate the valve, when the car is moving, the rpm is higher, and the sound will not be noticed.

And it worked.

The page also describes that any custom firmware will be overwritten, but I had nothing custom to overwrite.

Funny I should read this thread now... I just reported the problem to my Audi tech last week, and he immediately performed the firmware update while it was in having other warranty work done (failing right headlight ignitor)