Catastrophic engine failures?

[PixieVC]

I came across a thread on Audizine (linked here: http://www.audizine.com/forum/showthread.php/378538-Catalog-of-motor-issues-Catastrofic-motor-failure-information-count-update-12-03-11 ) regarding engine failure of a catastrophic nature for B6/B7 4.2 liter V8 engines.

They complain about a number of issues, such as broken timing chains (looks like a major architectural change from the RS6 4.2), and issues like broken rods, scorched cylinder walls, and other assorted issues.

Are RS6 engines susceptible to these same maladies, or would the unique handbuilt nature of the engines (and perhaps different design and architecture) play a role in keeping us immune from the issues that are being seen on the B6/B7 4.2 V8s?

Is the RS6 motor known for any sort of catastrophic failure mode different from the S4's 4.2 engines?

[MaxRS6]

Here is a bad story due to wiring harness

http://forums.audiworld.com/showthread.php?t=2817001

[4everRS]

There are some big differences in 4.2's through audi's lineup.

The rs6 has more forged peices in it than the normal units. The block itself is very similar to the rest however. The exhaust valves are sodium filled to take the higher temperatures of the boosted engine. I can't get them now but there are threads on the crank rods and pistons. Not 100% on this, but there were some that said they're not forged and were later proven wrong. I have yet to read about something real bad, like throwing a rod.

As Max said above, that was a bad deal. I have to imagine that there was a CEL or SOMETHING, that could have been a sign.

IMO the real reason why we haven't had more failure is due to the OCD servicing and quality of oil these engines have poured into them.

[mik15]

to be honest it's the first time i hear about engine failure to an RS due to a mechanical failure such as broken rods...i have friends with RS4 who used to really race it hard and didn't have any problems with it, i guess this kind of failures appear because they didn't stick to Audi's maintenance or due to over boosting the power to the point where the internals couldn't take it anymore and this combined with hard races results into mechanical failure which is predictable if this was the case...anyway, i don't think it's quite an easy job to destroy an engine which was designed to be pushed hard, they didn't just built the engine, i am sure it had to pass some serious and rigorous tests before entering into mass production...

[QuattroRS]

Different engine.

I will gladly change my timing belt and rollers every 35k over having that chain behind the engine. Gladly

I guess this means old C5 RS6s, S6s and D2 S8s will be getting more and more valuable. ;-)


I came across a thread on Audizine (linked here: http://www.audizine.com/forum/showthread.php/378538-Catalog-of-motor-issues-Catastrofic-motor-failure-information-count-update-12-03-11 ) regarding engine failure of a catastrophic nature for B6/B7 4.2 liter V8 engines.

They complain about a number of issues, such as broken timing chains (looks like a major architectural change from the RS6 4.2), and issues like broken rods, scorched cylinder walls, and other assorted issues.

Are RS6 engines susceptible to these same maladies, or would the unique handbuilt nature of the engines (and perhaps different design and architecture) play a role in keeping us immune from the issues that are being seen on the B6/B7 4.2 V8s?

Is the RS6 motor known for any sort of catastrophic failure mode different from the S4's 4.2 engines?

[PixieVC]

Different engine.

I will gladly change my timing belt and rollers every 35k over having that chain behind the engine. Gladly

I guess this means old C5 RS6s, S6s and D2 S8s will be getting more and more valuable. ;-)

Well this all makes me very glad I didn't pull the trigger on a B6 S4... I very nearly did...

I'm going to just forget about it, and enjoy the car... my mind is set at rest.

[vitalian]

Pixie, although there certainly are many potential weak points on the RS6 (e.g., transmission, torque converter, POS DRC suspension system), it is my understanding that the engine is not one of them. Although anecdotal, the absence of threads regarding catastrophic engine failures on this website seems to bear that out.

One of the members here once told me you could probably drop an RS6 engine out of a second-story window and it would be fine after minor repairs (not that I'm recommending that!!!). Although I seriously doubt that, it does seem that the engines on these cars are pretty solid.

[lswing]

I'm going to just forget about it, and enjoy the car... my mind is set at rest.

I try to do this at least once a week...and then go back to obsessing about something...

[4everRS]

Well this all makes me very glad I didn't pull the trigger on a B6 S4... I very nearly did...

I'm going to just forget about it, and enjoy the car... my mind is set at rest.
Belt = Better

Anyone know what the new 4.0tt uses?

[Chung]

Even thread titles like this make me nervous.

[ttboost]

Just checked both links. Interesting, but not earth shattering. Most of the failures you read about are caused by detonation, which is caused by a crap tune and/or an idiot driver (no offense if you are one) not listening to the signs. If you see a piston that has the top by the ring lands all eaten up = detonation, period.

One guy says he was just driving down the road at 40mph. Yeah, right...

[QuattroRS]

+1

I was going to say those guys should have been using Aces. ;-)




Just checked both links. Interesting, but not earth shattering. Most of the failures you read about are caused by detonation, which is caused by a crap tune and/or an idiot driver (no offense if you are one) not listening to the signs. If you see a piston that has the top by the ring lands all eaten up = detonation, period.

One guy says he was just driving down the road at 40mph. Yeah, right...

[PixieVC]

I try to do this at least once a week...and then go back to obsessing about something...

C'est la vie. I'm a car hypochondriac; I will always default to the worst case scenario for any minor hiccup the car makes - that is usually all in my head anyway. Obsessing over minutiae is a way of life when you're a computer geek... spills into other areas too. :jlol:

[Chung]

C'est la vie. I'm a car hypochondriac; I will always default to the worst case scenario for any minor hiccup the car makes - that is usually all in my head anyway. Obsessing over minutiae is a way of life when you're a computer geek... spills into other areas too. :jlol:

I was just telling a few this at beer night as well. I have a small leak and my friends laugh as I freak out. They have now said they are going to follow me around with oil and just make random oil spots below my car to see my reaction.

[papadoc]

Hey, are you related to Brian at BND or something like that? ;-)

+1

I was going to say those guys should have been using Aces. ;-)

[lswing]

Hey, are you related to Brian at BND or something like that? ;-)

I'm pretty sure ACES does not work at all....kidding kidding, here's to being safe with the engine!

[s42ski]

Iswing,

like the old add says - "try it you'll like it". Perhaps finding a user in the area you live in and doing a "butt dyno" test?? I was having difficulty buying the claims of BND as well, then I talked with Brian - who if he is not a chemical engineer, he can talk with one ( I have a friend that works at Chevron and had him on the phone - he now uses BND products!).

I also ran tests on his oil before putting it in the car.

Final bit - just did 75k service - plugs were clean, intercoolers were basically dry. All with BND

[QuattroRS]

Oh gosh can we take all this evidence from deadbeat engineers, physicians, and long term RS6 owners and say Aces is rubbish?

I dont have to pay for your pistons so choose wise.


Iswing,

like the old add says - "try it you'll like it". Perhaps finding a user in the area you live in and doing a "butt dyno" test?? I was having difficulty buying the claims of BND as well, then I talked with Brian - who if he is not a chemical engineer, he can talk with one ( I have a friend that works at Chevron and had him on the phone - he now uses BND products!).

I also ran tests on his oil before putting it in the car.

Final bit - just did 75k service - plugs were clean, intercoolers were basically dry. All with BND

[s42ski]

OK - so this "disgruntled engineer" also uses BND products...

What form of "evidence" would satisfy you? It seems oil analysis is not sufficient. OR is it you just trust large corporations to do what is "best" for the consumer...

[QuattroRS]

s42ski

I was making my point to those that continue to question aces. I don't have to pay for those pistons so let them do whatever.

I run aces. No brainer


Oh gosh can we take all this evidence from deadbeat engineers, physicians, and long term RS6 owners and say Aces is rubbish?

I dont have to pay for your pistons so choose wise.

[Elevens]

I must be a fool, I run Factory Spec Lubricants and Fluids. Haven't had an issue Yet. I hope I don't. I have a little bit of faith in the people that actually designed and made the engine. LOL!! To each his own I guess. Just my 3 cents......................

[QuattroRS]

I dont have a problem with factory spec lube or fluids.

I do have a problem with EPA mandate to keep increasing this crap ethanol percentage as they ruin our engines. 91oct CA fuel is complete garbage and AZ and NV are just the same. I dont know what the ethanol percentage is in FL but we are screwed on the west coast.

Dont even get me started on ethanol and the stupid reasons we choose to grow corn for fuel as we pump chemicals in our soil and water table just to provide a "green" fuel? So we die of cancer instead of green house gasses that may aid global warming?

[lswing]

I've been adding some Listerine, Wintergreen works best, damn does my car run great!

Honestly the ACES has been good, but I really need to get some 100 octane in, the real deal...

FWIW, cold crisp air the last few days, premium 92, wicked fast...turbos love the cold air!

[hahnmgh63]

Funny that it was mentioned, and the fact that I recently pulled my engine for a broken (my fault) Turbo Downpipe stud, and have used Aces IV for 3 years. I did take a vide (Snap-On video Borescope) of all 8 cylinders while the engine was out (mostly to test out the new fancy Borescope while I was replacing the plugs anyways, and because me (dummy) let drivers side cam spin a little while doing the timing belt so I wanted to inspect #1 valves on TDC). All cylinder walls looke almost like new, all valve seats looked very good with no noticeable deposits on the back sides. A small amount of cylinder carbon. Intake valve seats were shiny like new & exhaust (heat and/or composition (stellite or something)) were brown seats but looked good and not burned. I looked at & took video of all 8 pistons & 40 valves. I can supply the videos to anyone interested but some of the videos are large, anywhere from 25mb to 442mb. This was my first time using the beautiful Snap-On borescope w/SD card memory so it may not all look professional :) I'll continue with Aces IV and I'll do a cylinder Borescope every time I change the plugs just to be sure. So far so good and I am running greater Boost than stock on 92AKI / 97~98RON fuel w/ upto 10% Ethanol.

[kday]

I really don't want to step into this again, but I just have to point out that this proves nothing... you could just as well say that your cylinders look great because you only drive the car when you're wearing your lucky shoes.

FWIW I took apart a 220,000 mile AFC engine and the cylinder hone marks were still visible. Audi builds good engines.

[s42ski]

QuattroRS -

We see eye to eye on both the BND as well as our lovely "craptane gas" here in CA and the west. Ethanol works for Brazil, not for the US.

Elevens,

factory fluids that are changed at some interval (no lifetime transmission fill!) are good as well. I am not saying that the factory spec. product is no good! I think the BND is somewhat better. my 3 cents!

kday,

proof is hard to come by - what would be a good proof? We can run oil analysis, more Zinc means less wear, but also may mean issues with catalytic convertors later on, less aggressive towards engine seals is hard to measure.

Yes I am stepping into it as well:argue:

[kday]

QuattroRS -
kday,
proof is hard to come by - what would be a good proof? We can run oil analysis, more Zinc means less wear, but also may mean issues with catalytic convertors later on, less aggressive towards engine seals is hard to measure.


A bunch of people on a forum don't have the resources to do a scientifically valid study. Unless BND is an arm of a large corporation they likely don't, either. So instead we need to reason based on the available literature, and the ingredients in the additive. I don't see any detailed description on their web site. If we knew what was in it, we could do some real research.

It's a romantic notion that some guy in his garage can come up with a secret formula that does something that the major multinationals can not do, but that's not reality. That's not to say that engines or gasoline itself can't be improved by the aftermarket -- just that these improvements will be made by making tradeoffs that are not desirable for the mass market. ECU tuning is a good example: it's well known that fuel economy can be improved as well as power increased by changing the programming. This is not because of some secret discovered by aftermarket tuners -- it's because the fuel economy and power is gained by trading off emissions quality, which is a tradeoff the factory engineers can't make.

The first red flag I see on their website is this:


You will get better gas mileage – up to 14% better – and the engine will have more power.


While I won't say that this is impossible, it does stretch credulity that there is an additive that is effective at a 1.3% concentration that improves fuel economy without some significant tradeoff. If there was, it would come from the factory in a little tank like BlueTEC in a modern diesel, or it would be added at the pump. Auto manufacturers are spending enormous sums of money to improve fuel economy, and if this was a feasible approach it would be of extraordinary interest. So the possible conclusions I can draw from that are that 1) the claim is false or 2) the tradeoffs are significant, but undisclosed, or 3) the cost of the additive even at 1.3% is more expensive than (an "up to") 14% fuel economy improvement, even when manufactured at mass scale.

[QuattroRS]

Would anyone argue that fuel economy is generally less with ethanol blended fuels?

I seem to remember that a member performed a long term mpg test between crap 91/ethanol and Aces with the same fuel. Generally there was a increase of mpg with Aces use. I think approaching 10%.

Just an FYI. My car runs better with it....it may help....all the results seem to point that way....its not like I can go down to Audi and pickup another RS6.....life is short. = I'm fine with Aces.




A bunch of people on a forum don't have the resources to do a scientifically valid study. Unless BND is an arm of a large corporation they likely don't, either. So instead we need to reason based on the available literature, and the ingredients in the additive. I don't see any detailed description on their web site. If we knew what was in it, we could do some real research.

It's a romantic notion that some guy in his garage can come up with a secret formula that does something that the major multinationals can not do, but that's not reality. That's not to say that engines or gasoline itself can't be improved by the aftermarket -- just that these improvements will be made by making tradeoffs that are not desirable for the mass market. ECU tuning is a good example: it's well known that fuel economy can be improved as well as power increased by changing the programming. This is not because of some secret discovered by aftermarket tuners -- it's because the fuel economy and power is gained by trading off emissions quality, which is a tradeoff the factory engineers can't make.

The first red flag I see on their website is this:


While I won't say that this is impossible, it does stretch credulity that there is an additive that is effective at a 1.3% concentration that improves fuel economy without some significant tradeoff. If there was, it would come from the factory in a little tank like BlueTEC in a modern diesel, or it would be added at the pump. Auto manufacturers are spending enormous sums of money to improve fuel economy, and if this was a feasible approach it would be of extraordinary interest. So the possible conclusions I can draw from that are that 1) the claim is false or 2) the tradeoffs are significant, but undisclosed, or 3) the cost of the additive even at 1.3% is more expensive than (an "up to") 14% fuel economy improvement, even when manufactured at mass scale.

[kday]

Right, ethanol has a lower energy density than gasoline, so there is a mileage impact of a few percent. Alcohol also has a higher octane rating than straight gasoline, so it's not a total loss.

Has anyone logged the ignition advance under similar conditions with and without Aces? The only way I can think of that it would improve economy is if timing is being retarded without it. But at 1.3% I'm not sure how much of an octane boost it could give. Toluene for example is 114 octane and you need to use 10% to increase 93 octane base fuel to 95 octane.

[Hy Octane]

Aces is not an additive like octane booster. Its a catalyst. One ounce for 6 gallons chemically changes the fuel as compared to just adding octane molecules to it..
It is unlike any fuel treatment I have ever used..and I have tried all of them.. I get about 4 mpg more from a tank, the timing has advanced all the way so there is full power all thru the range unlike 91 pump..
Over 100 RS6 owners are using BND products with no complaints and no reports of any adverse reactions from it. Just give Brian a call and let him explain it to you. You will be impressed..or continue on as you are and miss out on how much better these cars can run with the right diet.

[QuattroRS]

There ya go.

Logging ign advance would be a simple test process. You just need the Vag//com and setup about 2 weeks worth of time and a similar commute those 2 weeks.

Week 1 with ethanol
Clear ecu/reset and drive all week with controlled fuel and mileage table.
Take vag data logs every day with a few standing start wot runs logged.

Week2 with aces
Clear ecu/reset and do the same

done


Right, ethanol has a lower energy density than gasoline, so there is a mileage impact of a few percent. Alcohol also has a higher octane rating than straight gasoline, so it's not a total loss.

Has anyone logged the ignition advance under similar conditions with and without Aces? The only way I can think of that it would improve economy is if timing is being retarded without it. But at 1.3% I'm not sure how much of an octane boost it could give. Toluene for example is 114 octane and you need to use 10% to increase 93 octane base fuel to 95 octane.

[4everRS]

I think I mentioned this in another recent thread were this came up. All this back and forth about ACES would be solved with a couple logs. Timing, EGT's, knock sensor voltage, fuel trims, ect. Needs to be a semi controlled environment, like temp and humidity. I may just end up buying another bottle again just to try it.

[Jimmy Joe]

I just don't get how some people don't understand why ACES IV is better for the RS6 engine than the regular OEM oil. I'ts like Brian says "It's an Armani suit for your engine".
Indeed it is !.If you mix the right components for a specific engine working conditions knowing the variables and adressing them properly, you'll always have a better fuel/oil,
no magic here. In other words, if you want a fuel additive or oil for general use, that is, for ANY car, buy off the shelf: If you want something specially tailored for your RS6,
buy BND. period. finito. kaput. over. genug ! basta. hametka ! ca suffit ! the buck stops here !

[QuattroRS]

Do....it...

But its more than just back to back tests. Need to determine a baseline then clear/reset ecu and add Aces for second test.




http://www.youtube.com/watch?v=lmUZGdi7Ty4



I think I mentioned this in another recent thread were this came up. All this back and forth about ACES would be solved with a couple logs. Timing, EGT's, knock sensor voltage, fuel trims, ect. Needs to be a semi controlled environment, like temp and humidity. I may just end up buying another bottle again just to try it.

[4everRS]

I just don't get how some people don't understand why ACES IV is better for the RS6 engine than the regular OEM oil.
To be clear, Aces IV is not engine oil. Quantum blue is the line of oil BND produces.

[Jimmy Joe]

Yes, 4everRS, my error, ACES IV is a gas additive, Quantum Blue is engine oil. But you get the point.

[4everRS]

I knew you knew it. Lots of people read this forum that may not.