Catalog of motor issues/Catastrofic motor failure, information/count update 12/03/11

[Justincredible]

Hey guys after my motor tear-down post and many months since then Ive been contacted by many a member with issues and pictures of there motor and its issues.

This thread is for anyone that had to replace a motor for any issue. Please PM me or feel free to post or E mail me. [email protected].

What I hope to do is help find and expose the issues, miles and damage that we are subject to. In my findings Ive came up with some serious, serious finds.

We are going to dispel one more myth right here today. At this point the weakest point in your motor...... IS YOUR PISTONS. That's right your pistons. Its not the rods its the pistons. Ive seen two motors with broken rods. They were both stock with bad cylinder wall scoring. You can see where the piston was binding up and then the rod just let go.

If your building your motor for power and you don't change your pistons your wasting your time. Even though we have strong rods it would be foolish to not get both new rods and pistons. The rods are strong but they have to kneck down to fit the stock piston. A new rod and piston combo would solve the weak rod and piston issue.

We all have read about issues with cylinder wall scorching?? what do you think is doing that? Its the skirt of the piston expanding too much. Ive seen it on several motors. Piston swell is nothing new and if you had cylinder wall scoring you might have witnessed it first hand.

So with that being said I would like to start a log of people here that have had motor issues. Serious motor issues. Please Feel free to post pictures and share stories.

Before reading below, please keep in mind the following. Some if these issues may have been from improper service by the owner. There are THOUSANDS and THOUSANDS (looking to get finnal production numbers) Of B6/B7 S4's and the largest collection of them are on this site so this may seem like alot but its a small fraction of the issues colllected into one area.

We can add a category if needed but the starting list looks like this.

Cylinder wall scoring or weak compression
04/ 3
05/ 7
06+4

Cylinder head damage / dropped valve / valve stem leak
04/ 4
05/ 4
06+

Lost piston / motor debris
04/ 2
05/ 5
06+

Bad cam tensioner/follower or adjuster
04/ 6
05/ 2
06+

Broken timing chain or guide
04/ 5
05/ 4
06+

Broken rod
04/4
05/ 2
06+3

This is a quick list Im looking through my notes for more causes. PLEASE feel free to share and I don't like to sticky my own work but if this gets going and you guys want it let me know we can put this up top for all to see.

Post still in the works.....

Comments or related posts to continue this thread are located here
thoughts and feed back

[Justincredible]

Digging for pictures to put here.

Examples.

Bent valves. Picture of the cylinder heads and the valves.



Picture of piston damage from valves hitting them



Picture of missing roller in roller rocker



Picture of Cylinder wall scoring



Bad motor debris total piston damage



Broken rod.

[jS4]

Justin, thanks again for your dedication.

Edit: this thread will scare me since my warranty ends in 31 minutes.

[Abwasserleitung]

2004 B6 S4 6MT Build Date 10/03 41k miles

Purchased 2/10 - Diagnosed 5/10 - New Engine/Car Returned 8/10

Engine replaced due to:

Cylinder wall scoring and weak compression (20% loss on two cylinders)

Bent Valve stems

Broken timing chain guide

[SquiddyB6S4]

2004 B6 S4 6MT Build Date 10/03 41k miles

Purchased 2/10 - Diagnosed 5/10 - New Engine/Car Returned 8/10

Engine replaced due to:

Cylinder wall scoring and weak compression (20% loss on two cylinders)

Bent Valve stems

Broken timing chain guide

Justin, your statement about piston swell is making me wonder which came first here. I wonder if the pistons swell, causing undue stress on the timing chain, which may actually cause some or most all of the timing chain area issues we see on these cars. Or are they unrelated? Just some food for thought.

Also, I suggest that you put at the end of the list an approximate number of actively-posting members with B6/B7 S4's on this forum. Say, the number of members who have more than about 10-20 post count, and have posted something in the past 30 days. This just to keep from counting people who aren't active any more, and keep from counting the kid that joins, asks one question about a car he doesn't actually own, then never shows up again.
I think this would help keep it in perspective, how common or rare these sorts of issues are. For instance, saying that there have been 10 motor deaths might sound intimidating, but if we have 1,000 owners on this forum who are running along just fine, all of a sudden 10 motor deaths is nothing new or special from any other car. If we only had 50, then yes, 10 motor deaths would be just crazy.

[deviant-customs]

2004 build date 10/03
Cam follower fell apart
41k

[drew]

2005

High oil consumption and scored cylinder walls

New long block by cpo at 86K miles

[slo s4]

Great idea, thanks again for everything you are doing to advance our poor little unloved platform. "Slow" V8s are starting to not be so slow due to you, and people like you.

[EssPhore]

2005 CPO

High oil consumption, several scored cylinders

Engine replaced at 75,000

[Bpitz15]

2005 6MT.

New shortblock and rebuilt heads due to high oil consumption from leaking valve seals and scored cylinder walls.

I've heard the cyl wall scoring could be from improper break-in from the first owner. The car had 41k.

[halik]

04 100K miles, catastrophic #8 failure. I never seen the original motor, but the audi tech i spoke with said he could see the rod though the spark plug hole.

[SuperAvant]

112K Miles - High oil consumption but cause hasnt been determined yet.

[Justincredible]

Curious, as my latest oil analysis showed above-average aluminum. Blackstone speculated this was from the pistons but also thought it could just be from the repeated autocross/track days it saw.

Keep em coming guys. Im updating the list. This kind of format makes it very easy for me and others to read... Thanks guys

2005 CPO

High oil consumption, several scored cylinders

Engine replaced at 75,000

dparm. Try running a 100% pure synthetic. Amsoil/ELF Along that kind of brand. Then let us know. From what Im seeing. Even if people do have aluminum in the oil. The Higher Syn oils seem to help stop or Control this better

[AndyGs4]

04 Build Dec 03.

Disintegrated a piston in Cylinder #4.

[BCsniper]

I am kind of shocked at how many of you have had to have your engine replaced at one time or another.

[SpeedETC]

2004 with an 02/2004 build date (purchased new - currently 114k miles).

High oil consumption developed at 110k. Compression normal, no cylinder scoring. Found a broken chain guide when after the motor pull. Replaced all the valve stem seals, chains, guides, tensioners. The consumption has dropped.

Oil changes were done every 5000 miles.

[littleredwagen]

05 S4 6MT
Valve Guide failure in Cylinder 8(ovaled out) and subsequent valve seat damage, High Oil Consumption in Cyl. 8.
engine had 86k on it

Second V8 has high oil consumption in cyl.3 leading to misfires due to fouled spark plug.
Second motor is 04 V8

[Justincredible]

Thanks to everyone that has and is posting there information here. Please encourage other members that you know have had issues or if you find old posts. Please have them put there information here or feel free to post a link to past posts with people and there story's.

If any one wants to comment or continue a discussion please make it in this post
Motor failure conversation post

[gdawg'05a4]

2006 w/ low compression and oil consumption (1 qt/500 mi). Currently at 74k miles. Test results (dry and wet):

Cyl 1: (D) 110, (W) 150
Cyl 2: (D) 125, (W) 170
Cyl 3: (D) 110, (W) 148
Cyl 4: (D) 125, (W) 170
Cyl 5: (D) 140, (W) 177
Cyl 6: (D) 135, (W) 170
Cyl 7: (D) 123, (W) 147
Cyl 8: (D) 125, (W) 150

Noticed excessive carbon on all pistons. Cylinder walls were fine, no scoring. Suspecting piston rings are stuck, performed a piston soak to clean up the carbon. Monitoring oil consumption now, logging level via vag-com and dipstick every morning. So far it looks promising at 250 mi since doing the clean up.

[SuperAvant]

^^ Does Lee think its the oil collection ring getting gummed up? The deviation of your numbers is interesting.

[gdawg'05a4]

^^ Does Lee think its the oil collection ring getting gummed up? The deviation of your numbers is interesting.

Yeah we think its the rings that are stuck. So far the oil consumption seems to have gone down. I will know in 200 mi whether it still consumes a quart. But so far I've been checking the level every day since we did the test and there is little to no change.

[tonyd727]

05 52K with scored cylinders found by compression test. Oil consumption 1 quart every 800 miles

[MaudiS4]

04 97500 miles Cylinder #8 1 Intake valve broken / Piston damaged

[drew]

j, you should sticky this

[jfunkey]

j, you should sticky this

2nd... Drew knows best and Im in 100% agreement with him.. Also please keep trimming the posts for the extra stuff.. The conversation stuff works well in another thread.
I like how this is just the list... Great work

[Carlos Finighan]

Put down one more for rod and scored walls.

B7 48000 miles
bad rod through block and scored walls

This should be a sticky.

Ive seen lots of issues that are on the list. I feel it would be wrong to share any more then what I have first hand experience with.

People should know that there are issues with any motor in any make of car. There is not a issue so large that there is a recall or dealer worry.

If you want to keep the car healthy, Use a full synthetic oil and change your oil in accordance to your driving style

The issue with the tension-er, There is a sleeve where the tension-er rises and falls as needed. Its a wearable part, good oil and regular changes should keep that part healthy for a long time

[beemercer]

^Similar advice as to what a gentleman who works in the OEM and aftermarket industry gave me. It just sucks getting a used car with an unsure history.

[manhattanprjkt8]

X-Post From the Engine Pull Thread I Posted

Wanted to put a quick thread up outlining my recent experience with my 2004 4.2 S4…I know there have been tons of threads regarding chain tensionors and a motor pull.

About 2 months ago I began experiencing some concerning issues with the car

- Start up noise began to get noticeably louder, it always had some but this was increasingly loud.
- Began have a click occasionally coming from the engine at low idle speeds
- Noticed adding oil a bit more often than normal but nothing to concerning.

Like I said above nothing was so concerning that I felt I needed to take the car to the dealership right away. That is until the engine light came on…I had the car at the dealership 4 times and they did multiple things to the car. Coilpacks, fuel injectors, and a carbon clean each time resolving the code it was throwing but the light would come on days after getting the car back.

One day the engine light came back on and began flashing the car basically went into limp mode, so I shut it off and had it flat bedded.

The Bad News – ‘Sir we are going to keep your car for a while and it is going to get rather expensive’, I knew exactly what that meant. I just received my car back the other day and here was the basic summary of repairs:

2 Cracked Tensioners
2 Bad adjusters – which caused the leaking oil.

After the motor pull it did get rather expensive but not to the level I expected, dealership treated me great and it was about as much of a positive experience as you could expect from news like this…

[Justincredible]

Thanks guys updated

[Tony951]

2005.5 S4 bought at 63K miles from used car dealer - turned out #5 cylinder wall scored, compression down to 50psi, high oil consumption, borascope confirmed scoring. Replacing engine.

[beemercer]

2005.5 S4 bought at 63K miles from used car dealer - turned out #5 cylinder wall scored, compression down to 50psi, high oil consumption, borascope confirmed scoring. Replacing engine.

With some killer goodies .

I saw you tried to PM me, I emptied my PM box so now I can receive messages.

[stedsS4]

2004 S4, 6-speed, 55K miles - dealer just pulled engine/transmission and replaced 4 timing chains, cam adjusters, tensioners and all the related parts (gaskets, hoses, rails, tracks, etc). Engine light was on (codes below) - low compression in one cylinder bank - rebuilt both sides since it was all out of the car. Cam was offset by almost 20 degrees. Also had the ribbed serpentine belt and slave cylinder (clutch) replaced. Dealer had car for 2+ weeks. Cost $9,500. Got a nice box of old parts as a parting gift!

6 Faults Found:

16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 008 - - Intermittent
16685 - Cylinder 1
P0301 - 008 - Misfire Detected - Intermittent
16689 - Cylinder 5
P0305 - 008 - Misfire Detected - Intermittent
16686 - Cylinder 2
P0302 - 008 - Misfire Detected - Intermittent
16691 - Cylinder 7
P0307 - 008 - Misfire Detected - Intermittent
16405 - Bank 2: Camshaft A (Intake)
P0021 - 008 - Retard Setpoint not Reached (Over-Advanced) - MIL ON

Also of note, dealer did the coil pack recall and plugs about 4 weeks prior to engine light coming on - don't know if this pushed the timing issue.

[SoCalS4Avant]

We're going to sticky this up top while we look to catalogue these issues, as well as call atention to potential issues for new/future owners. Please add info as neded. We can update the original post as it comes in.

[vdubinteriors]

Brand new short block at 64k

9 quarts of oil per 3 weeks

Scoring of three cylinder walls

Now have 3k miles on new short block - running good so far

[Justincredible]

Brand new short block at 64k

9 quarts of oil per 3 weeks

Scoring of three cylinder walls

Now have 3k miles on new short block - running good so far

Year please

[93hrdtptt]

'04 1 quart per 300miles.

cylinder 6 + 8 scored, low compression, oil on plugs - 5,6,7,8

[chaos2984]

I have a 05.5 b7
with 80K on the clock and she runs great and i
burn 1 qt about every 1500 2000 miles or so.

i have some timing chain rattle at cold start up for a few seconds when the oil is worn out. I run mobil 1 0w40. I love this car and would'nt trade it for anything unless it was an R8 lol I think proper break in with the new owner is key with these motors

[timmmy]

Hi All,

The 05 BHF motor in my S4K race car lost chunks of both cyl 5&6 pistons last weekend. Confirmed wiht a Boroscope.

I dropped this motor into my 4K, motor was from a 2005 S4 cab, stored motor for a few years. Prior to initial startup cold compression was goodish (150ps +/-10 across all 8). Ever since first startup I have been struggling with excessive deceleration blowby btu had not rechecked compression. Proir to last weekends event I checked compression cold and found cyl 5&6 were down to about 120si cold. Ran the track event and by the end of it the hot compression on those two had dropped to 90psi :(

[Justincredible]

not idling and being driveable at all in which was believed it was a timing chain tensioner & guide issue.

2004 Manual.

Build date is 10/03

Mileage is little over 80K

Adding information broken chain guide

[yohimbe2]

add scored cylinders at 33K to the list. 2007 B7 S4 motor headed for the dumpster.

While at the shop, another car/ engine was on its way to the dumps. Same car, low mileage.

Audi needs to figure out what they did wrong here. I would love an explanation.