2012 S4 Horrible Noise After Oil Change (customer states) Need a super Audi hero !

[VAGBAHN]

Figure out this noise and you're top dog ! Audi tech have looked and watched the video and the response so far "WTF" 2012 Audi S4 3.0T, Customer states that immediately following an oil change , a clattering noise was heard. The noise is consistent and does not change pitch with rpm increase. The customer drove the vehicle approximately 50 miles after this incident. The vehicle was taken to a shop in the community near us where a partial disassembly was performed (rear upper chain covers) to expose the upper timing chain tensioners. The findings were- missing and broken chain guide pieces for bank 2 cam chain. The noise described was not commensurate with a chain scraping on a guide, therefor it was assumed to be a collapsed hydraulic tensioner. The vehicle was brought to our shop where the transaxle and rear timing chain cover were removed. There was no obvious damage however on disassembly inspection of the timing chains, the bank 2 exh cam sprocket was found to have several indentations where the chain had been pressed into it. The suspect was the detached chain guide pice (plastic) which may have wedged in between the chain and the sprocket for several revolutions before falling into the oil sump.
Both bank 1 and 2 upper hydraulic chain tensioners were replace, bank 2 exh cam sprocket and upper chain + lower chain hydraulic tensioner were replaced. Balance shaft spun freely and noise free when opreated via high rpm drill. After completing the work the transaxle was reinstalled and the engine started...SURPRISE ! , Noise still there . Transaxle back out + engine started w/o transaxle in place to observe. See Video ... yes ... WTF ?

[AKPS4]

Yikes. Nothing is good about that one. How about removing the charger and inspecting the intake and exhaust valves/openings? Given all the work already done Taking the supercharger off is not that much more work.

[theswoleguy]

Yea sounds like valve piston contact. You stated timing chain issues. Could be loose flywheel is dual mass and had them fail on my gti

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[cspcrx]

Does the sound change with RPM?

[pdqgp]

Customer states that immediately following an oil change , a clattering noise was heard. The noise is consistent and does not change pitch with rpm increase.

Sounds to me like the customer is holding back a wee-bit. Call me a skeptic but things like that don't just happen.

[cspcrx]

Unless they used some type of siphon system and some part of it came off and is in the motor getting wacked by a rod or the crank.

[VAGBAHN]

Removed charger belt and ran the engine ... no change. As far as the dual mass, what you see spinning is the flex-plate. The clutch module stays with the trans on the 0B4 style gearbox. There was never any crank/cam correlation fault and compression is perfect.
The sound/pitch does not change with RPM. When I put the camera up to the running engine you can hear the sound increase a bit at the top of the flex-plate. The only thing spinning directly behind there is the balance shaft. I removed the balance-shaft chain and ran spun it with a high speed drill connected to a socket; nothing. I looked at all of the fastening bolts to see if any had markings from going too far through the rear of the block and possibly hitting a piston or counterbalance on the crank. Everything looks great , no metal in the oil, not a scratch on anything visible. The odd thing is that you don't get to hear it when manually rotating the motor...it's only when it's running .

[chaos2984]

Have you taken a stethoscope and listened all over the engine to see if you can localize the noise to an area in the engine? Thats what I would do. Sounds like some sort of slapping. you turn the engine over by hand and no binding? I would try to run it without the valve covers on and see what you got. Or atleast crank it and not fire it and see if you can tell anything.

Have you taken the flywheel off the engine. Sounds like something could be behind it also. Im guessing its a manual right?

[Sceanzo]

Seems impossible that isn't RPM dependant

[VAGBAHN]

Have you taken a stethoscope and listened all over the engine to see if you can localize the noise to an area in the engine? Thats what I would do. Sounds like some sort of slapping. you turn the engine over by hand and no binding? I would try to run it without the valve covers on and see what you got. Or atleast crank it and not fire it and see if you can tell anything.

Have you taken the flywheel off the engine. Sounds like something could be behind it also. Im guessing its a manual right?

Yes, it's manual. I needed to keep the flex plate on because the ring gear for the starter is on it. My first thought was that it was the plate hitting something . Odd that nothing strikes when turning it manually.

[Sceanzo]

It isn't in the rotating assembly if it won't change with RPM.

[chaos2984]

Yes, it's manual. I needed to keep the flex plate on because the ring gear for the starter is on it. My first thought was that it was the plate hitting something . Odd that nothing strikes when turning it manually.

Have you taken the flywheel off at all. It sounds to tinny to be inside the engine. i would remove the flywheel and inspect and see if there are rub marks on it or if anything falls out from behind it. Any moving parts to that flywheel?

I would thoroughly inspect the flywheel and area if nothing there get a mechanics stethoscope and poke around and see if you can pinpoint an area where the noise is the loudest.

[Sceanzo]

Have you pulled the oil filter? I am betting some sort of engine starvation has cashed a valve train component like a rocker.

[Luna's S4]

I heard a similar noise many years ago, from the top end of a DOHC after a rebuild I did. It turned out to be valve guides not properly knurled and reamed which led to out of center bores. Since that is not likely here, I am guessing bent valve(s). This would possibly be consistent with a skipped chain. That sound sure sounds like metal scraping metal, in my opinion. Captain Obvious.

[chaos2984]

Well since you say it does not change with rpm at all. It has to be nothing that has to do with any of the rotating engine components. I would poke around with a stethoscope and see what you come up with

[Luna's S4]

Read that too. With my experience it didn't seem to, oddly, make "much" difference with RPM change. Just sounded horrible no matter what. I know that does not make sense but with 24 valves moving it might not be as easily discernible. I dunno...

[eurotic]

Can you hear the noise when cranking the engine over?
You say that revving the engine has no effect on the noise, correct? It doesn't increase in tempo?
Could it be injector noise? I know it is unlikely but at this point I think we are looking for out of the box items right?
What about a blown mount? With the engine running you could apply pressure to the front or sides to see if that changes anything.

Too bad you can't run the engine with the flex plate and covers off like in post #7

[chaos2984]

Its not going to be a mount issue. Since he has the trans off the engine is not in the correct position anyways more or less. So your going to get some ground out. But to me without seeing it in person. It sounds like a flex plate noise on any other car rubbing on something with the tinny noise. And yea that would be good to run it without the covers on it but its going to make one hell of a mess with pressurized oil squirting everywhere. (that's how the chains and guides get lubed)

[eurotic]

It sounds like a flex plate noise on any other car rubbing on something with the tinny noise.

I agree with that but based on the info that the sound doesn't change with increased RPM is suggests it can't be. But I would be going back to the flex plate if it were me. Or trying to get the engine running without the plate...not sure that would be possible or safe to do though.

[BoostEasy]

Sounds like a metal tool fell down in some crevice on the engine and may be rattling around. Makes some sense too since it was supposedly just an oil change. Very hard to tell though without really being there and hearing it.

I like the stethoscope idea (a 2' length of std rubber hose like 3/4" will do).

Owner or shop that did the oil change could be withholding info too.

Best of luck with it.

[VAGBAHN]

I agree with that but based on the info that the sound doesn't change with increased RPM is suggests it can't be. But I would be going back to the flex plate if it were me. Or trying to get the engine running without the plate...not sure that would be possible or safe to do though.

We have had 5 sets of professional eyes take a look around, even an Audi manager. The flex plate is not warped, cracked or obstructed by anything. All rotating visible parts have been looked at under a magnifying glass and there is no visible metallic particles in the oil. I can't think of a good way to start the motor without the flex plate ..and I wonder if it would even run given the need tor external rotating mass to transition through compression. I'm sure the flex plate is acting like a speaker for what ever omni-directional noise comes from the crankcase. If I don't get a hit on this soon I will be suggesting crankcase tear down... I'm sure the customer doesn't want to go there but there is no crystal ball for this.

[chaos2984]

We have had 5 sets of professional eyes take a look around, even an Audi manager. The flex plate is not warped, cracked or obstructed by anything. All rotating visible parts have been looked at under a magnifying glass and there is no visible metallic particles in the oil. I can't think of a good way to start the motor without the flex plate ..and I wonder if it would even run given the need tor external rotating mass to transition through compression. I'm sure the flex plate is acting like a speaker for what ever omni-directional noise comes from the crankcase. If I don't get a hit on this soon I will be suggesting crankcase tear down... I'm sure the customer doesn't want to go there but there is no crystal ball for this.

You can run the engine without the flex plate. The harmonic damper will suffice. But you have to start it someway. Before you tear anything down get a stethoscope and poke around. KD or Lile tools make what I'm talking about. This will work http://www.sears.com/kd-tools-mechan...p-00999911000P I would poke around with that and see if you can find a location where the noise is in general area before mad scientist tear down. Im sure you took the serp belt off and ran the engine and noise still there right?

[VAGBAHN]

You can run the engine without the flex plate. The harmonic damper will suffice. But you have to start it someway. Before you tear anything down get a stethoscope and poke around. KD or Lile tools make what I'm talking about. This will work http://www.sears.com/kd-tools-mechan...p-00999911000P I would poke around with that and see if you can find a location where the noise is in general area before mad scientist tear down. Im sure you took the serp belt off and ran the engine and noise still there right?

The noise must be crank related because the harmonics are only audible from the flex plate which is sort of thin and I believe it's acting like a speaker. In the mean time it's coming off the lift so I can eat...these things kill a month of income when they happen ;(

[timzcat]

I agree it's not rotating mass which also includes top end, no bent valves or anything. Step back and look at the cause, an oil change.
The noise is at the top of the engine, ironically so is the oil filter, I am surprised you did not replace it by default. Always go over the work that caused the problem.
My guess is something is bouncing around in canister or improper assembly, especially if owner went to a quick lube.

[Sceanzo]

It isn't in the rotating assembly if it won't change with RPM.

Have you pulled the oil filter? I am betting some sort of engine starvation has cashed a valve train component like a rocker.

Well since you say it does not change with rpm at all. It has to be nothing that has to do with any of the rotating engine components. I would poke around with a stethoscope and see what you come up with

I agree it's not rotating mass which also includes top end, no bent valves or anything. Step back and look at the cause, an oil change.
The noise is at the top of the engine, ironically so is the oil filter, I am surprised you did not replace it by default. Always go over the work that caused the problem.
My guess is something is bouncing around in canister or improper assembly, especially if owner went to a quick lube.

😐😐😐😐

[VAGBAHN]

Okay Sceanzo, I think you've encouraged me to think outside the box on this but here it goes .. Yes I checked the filter, "FIRST " thing I did. This car belongs to a dealer. They changed the oil. Being a dealer I'm wondering if they washed the engine or engine bay; here is why .. According to my latest conversation with the owner; the engine as not making noise immediately after the oil change, but after the test drive by their car lot technician following the oil change.. I am now wondering what happened on that test drive. 1. Was there water in the air box that got sucked in during the test drive , slightly bending a rod via hydraulic condition of one cylinder? 2. This is a 6 speed manual, so could a downshift into first at a high speed wound up the RPM too quickly which spikes oil pressure (which has been the culprit in many rocker failures) in FSI -TSI VAG applications ?

[cspcrx]

I would lean towards a miss shift more than sucking water in. The box has a drain hole in it and water would have to fill up the entire box and not drain out.

[jsh139]

If a rod were bent, wouldn't the sound change with RPM?