the v10 s6 project

A6 All/ S6 All
#321

That’s a great update. The good news is you are finding a good direction and data. I’m guessing also from how you worded your post that this isn’t your full time DD and you drive it off and on. That can make things difficult to track down.

So this is what we can take from the data we have so far.

Running on no mafs puts the car into open loop and only reads from the 02s for input. So make sure to check your 02 voltages and AFR reading to make sure everything is good. espically since you got an 02 code.

Usually disconnecting the MAFs and getting the car to run better means you have a vac or intake leak somewhere. It also makes the car run a little richer so keep that In mind. Check your long term trims last time you had I have one bank at 25% positive and one bank at %25 negative (maxed out) on the partial fuel trims,

The car will never come out of the open loop so that means its not reading off all the sensors so if you can drive the car with no issues that is something to think about.

#322

Do you mean it is not reading off all the o2 sensors? Or are you referring to the disconnected MAFs as sensors?

#323

Sorry for the crapping wording on that. open loop isn’t taking into consideration incoming air temp air density and I don’t think it adjusts for coolant temp feedback. So normally the car is taking fuel adjustments off all the sensors but in open loop it uses the 02 strategy feedback but not looking at some of the other sensors might help be the thing that’s keeping the car from adjusting fuel incorrectly.

#324

Interesting… I just checked some of my old logs, and I did have one occurrence of

000275 - Intake Air Temp Sensor (G42)
P0113 - 002 - Signal too high

I think Ill change that sensor too, since they are pretty cheap.

It is just crazy how well the car is running now with the MAFs unplugged. And considering that, it would seem that the one group of components that is functioning properly is the o2s.

That being said, even though from the symptoms it doesnt sound like the o2s causing the issue, Ive ordered them anyway and will have them all swapped. Unfortunately, regular troubleshooting hasn’t resolved the issues on my car, so Im forced to move forward with the ‘brute force’ method, and just replace everything that is suspect with new parts.

#325

well its hard to say that the 02s themselves are not part of the issue. wisdom would tell you that if you unplug the MAFs and the car runs well or better than before that on the intake side your pulling in un meatered air and that was casuing an imbalance and due to your LTFT data that looks like it might have been the case…

but…that might not be the case all the time. Here you are defaulting to the 02s only but you really should check to make sure your 02s are adjusting and see what your LTFT trims are now. The car is running richer without the MAFs plugged in and that might be covering up a possible LPFP issue or a rail pump issue. So its helpful to gather as much data as you can. Right now one thing is certain the car mechanically is able to run misfire and issue free when its not looking at all the sensors. Now figuring out what sensors and why will help you get closer to your end goal.

I don’t know all the parts you changed but look into new MAF sensors and also keep in mind. Some people have replaced expensive things like injectors in the past only to have the new injectors still be bad. It can be a hard road to walk down but you are doing it right. replace parts that make sense to replace so you can check that off your list. Sooner or later you will find the bug and the best part of that is once you do you will have a trouble free car with a list of needed maintenance parts replaced in the meantime.

You mentioned that you got an 02 code so you would need to replace some of the sensors anyways. It sucks when you have 8 of them but if your replacing one you really should replace them all.

#326

It stinks the car is not running right. I have had my car since 2011 and have put in nearly $13,000 in and this does not include the custom manifolds and exhaust or tires.

The car at first had misfires, then started leaking oil. Did a complete tear down of the motor, replaced all seals and maintenance parts. http://audirevolution.net/forum/index.php?topic=4228.0

The heat this engine produces does not help either.

#327

Any updates??

#328

Hello All,

This is my first ever post on AudiRevolution and I just wanted to say that this thread and the years of work that went into the final product have captivated me. This however, also leaves me with questions.

I obviously, reading through the pages, realize that none of these systems are NOT for sale anymore. However, I was wondering what the name of the shop is that did the work. I went through the thread 3 times, re-skimming, and I only ever see it referenced as ‘The Shop’.

I’d love to know because I live less than 25 minutes from Detroit and I know that’s where the shop was. Can anyone enlighten me to the name of this shop?

I have an C6 S6 and I’d love, if this shop would even be interested in it at this point still, to see if I could get the same type of work done on mine.

All that aside, v8a6, your story and the time and effort put into this is remarkable and the finished product is amazing. I hope you get these final bugs figured out soon so you can finally fully enjoy the fruits of your labor.

Thanks,
Razgriz

#329

In honor of V8A6 and his car one of the other header cars has had its results made into a video

http://audirevolution.net/videos/198/audi-v10-s6-w-headers-and-catback

razgriz10000

For the headers you would have to contact countvohn. Him and his fab shop make these headers. They do it on a case by case basis. If they get backed up they usually will not take on new work so keep that in mind.

#330

My god… it’s like a rocket ship every time. :’)

#331

I need to hit the lottery or work way harder so I can afford a set of those headers and the install lol… someday down the line maybe.

#332

V8A6

Wow what a saga. Thank you for sharing. This thread needs a soundtrack!

https://www.youtube.com/watch?v=bfV_IdhPG0s

Cheers!

#333

Did they move the Front O2 sensors? I don’t see them in any pic

#334

Yes all of the 02s were moved to help in easy removal if needed.

#335

So what’s the latest on the build here? How many other headers were made as a result of the original efforts. I know Nordy had some similar ones built but that was after the initial builds here.

#336

V8A6, did you ever end up adding the RS6 side skirts? I’m interested to see what they look like on the S6.

#337

Sorry, never got around to having them installed. Same for the RS6 front bumper.

Will see what happens. I working to finish everything off, and the bumper and side skirts were part of that. If I decide to skip, Ill post for sale as a package. Along with the front bumper I ordered a Euro impact beam and supports, as the front NA one didnt line up.

#338

Once done and complete, and tuned I don’t think you will want to sell :wink:

#339

Are there any videos of V8a6’s car in action or any sound clips or dynos? Id really like to know how much HP he gained off of them giant headers he built. id love to have a set of them too are they still for sale? can they still be made?

#340

Headers alone is probably 30-50 whp. Stock headers and cats suck. 600 cel and right by the motor. You’d have to pm countvohn if you want headers. Look up nordys build he’s done pretty much all the powertrain mods sans supercharger. Headers or at least gutting cats and tuning appropriately is worth it if you have done all the other JHM mods.