need some advice about 2.7t misfires

[V1nny]

Last week got my car after more than 2 weeks in the shop, and my misfires were not fixed, CEL come back later same day.
Car is 01 allroad with manual transmission, basic stage 3 (was working fine for couple years before misfires started), and bunch of other mods including
3" downipes, magnaflow, cat-back and SAI/EGT/rear O2 coded out.

I have no ide what else to do to fix the misfires as everything possibly related was replaced including
MAF,
spark plugs (4 times, all kinds of gaps and different plugs)
injectors (Bosch green giants)
ignition coils (replaced twice all of them)
last week replaced ECU, same stage 3 flash by Josh from Solo motorsports, believe it was totally unnecessary, shop's idea..
All cylinders compression seems to be good, was checked 3 times by different shops in the last 4 months

One option I am looking at, is to find low mileage engine, and transfer my K04 turbos on it. Or maybe there is still a chance to fix the misfires? Any ideas?

Here is what I have either before or after latest "repairs":


Saturday,12,December,2015
VCDS Version: 12.10.3

Address 01: Engine Labels: 078-907-551-AZA.lbl
Control Module Part Number: 8D0 907 551 M
Component and/or Version: 2.7l V6/5VT G 0002
Software Coding: 06711
Work Shop Code: WSC 87119

6 Faults Found

17965 - Charge Pressure Control
P1557 - 35-00 - Positive Deviation
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 -
16688 - Cylinder 4
P0304 - 35-00 - Misfire Detected
16690 - Cylinder 6
P0306 - 35-00 - Misfire Detected
16689 - Cylinder 5
P0305 - 35-00 - Misfire Detected
16686 - Cylinder 2
P0302 - 35-00 - Misfire Detected

Readiness: 0000 0000

[Slow4]

Maybe it's the solowerks tune; did you try running it without the software


Royale W/ Fromage

[V1nny]

Maybe it's the solowerks tune; did you try running it without the software


Royale W/ Fromage

I run with this file from early 2013 till sometimes late spring this year for about 25K miles, and really liked it, 0 misfires. On the shops suggestion, I bought a used ECU last time, sent to Josh, and he flashed it again with same file last week. He knew what the issue is (myseld and shop emailed him all details), but it never occurred to him to adjust anything in the file.

[drumnjuny]

i love how you have an issue you cannot diagnose yourself, willing to pay someone else to diagnose, and then willing to slam them when their efforts didn't work. you can't fix it right, so why are you bashing someone else for not being able to? Don't take your car places for diagnosis of issues you don't understand then... because guess what's gonna happen every time. they're gonna spend time on it and then you're going to have to pay for it whether or not they fix the issue. they didn't work on your car originally, they have no idea what the issue is either... you've had the issue forever and then gave them 5 days before freaking out. sounds like you are an impossibly difficult customer, i would have turned you away at the door.


that being said... buying a whole new car seems a little absurd since 2.7's are dirt cheap so it might be worth picking up a motor and then swapping out sensors and parts until you figure it out. after your list of things to be done its time to break out the multimeter and see if any of your harnesses for the related sensors are shorting out or shot (you didn't list MAP but i presume you looked at that as well). check for vacuum leaks... smoke test for exhaust manifold leaks... maybe PCV is clogged if you have one?

is the car tuned to use the MAF reading or density volume? if its tuned to use the MAF, you would be popping cel's for underboost/overboost (unless your tuner has removed all the standard safeguards). What are the conditions under which you are misfiring? All the time? Or just under WOT? need to take logs during misfires so we can get more info. at what MAP pressure / MAF reading, at what throttle, injector timing, ignition timing...? are you misfiring too lean or too rich? the answers to these questions will help you narrow down where the issue is.

[V1nny]

car was in the shop for over 2 weeks, not 5 days: dropped off November 25, picked up on December 11.
Thank you for listing all diagnostic steps, but why would the shop where my car was for two weeks, and charged me over $500 would not do them?
For now found a 80K motor in PA for about $1000 delivered, waiting on VIN from seller to make sure miles are real.

as for "you can't fix it right, so why are you bashing someone else for not being able to?"
in that case thy should have told me: Sorry, we were not able to find what the issue is in the two weeks car was in the shop, there is no charge..

[drumnjuny]

car was in the shop for over 2 weeks, not 5 days: dropped off November 25, picked up on December 11.
Thank you for listing all diagnostic steps, but why would the shop where my car was for two weeks, and charged me over $500 would not do them?
For now found a 80K motor in PA for about $1000 delivered, waiting on VIN from seller to make sure miles are real.

(1) again with the bashing of shop. you've had this issue for how long again? and compare that to two weeks one week of which is thanksgiving, a holiday upon which most people especially small businesses do not work?

(2a) you said XYZ had been done. I was suggesting steps aside from the 4 things you mentioned. This is a motor vehicle not a computer mouse - lots of electronic and mechanical pieces integrated together. you're going to have to try harder than that. if you don't have logs you haven't even started to diagnose the issue - if you don't know what's wrong swapping random parts is not the most effective way to fix this. and i don't think i know any shop that's gonna take a stage 3 car that runs like ass and go romp on it and risk blowing it up, especially when dealing with a customer with unrealistic expectations...

(2b) $500 doesn't buy shit for labor... basically anywhere in the DMV. plus seeing how ridiculous you've been so far i'm gonna assume part of that $500 was the cost of a new ECU. Which by the way, is a pretty reasonable thing to swap since you act like you've exhausted every other option of what it could be. the only reason i didn't mention it is because you said you already touched it

(3) you can get a 2.7 cheaper than $1000, but okay.

(4) i rescind my implied offer to help diagnose this issue because with how absurd you are being, soon you'll be bitching about how i didn't fix the issue either. good luck.

[V1nny]

I paid for used ECU ad overnight shipping separately, so $518 charges were for diagnostic and set of cheapest copper plugs, which did not fix anything anyways.
I do contract work myself as a computer engineer, and cant imagine situation where I would bill my customer $500 for literally nothing.
Two weeks is a lot of time, and when saying to weeks, I already accounted for Thanksgiving..
I really started this to get some advice, not to bash anyone, not sure why anyone would blame me for anything.

[drumnjuny]

if your focus was to get advice, then your response to my first post would have been "here are the logs" or "i will take logs ASAP and not waste everyone's life posting slander until i do"

not state they did nothing, after stating they did replace the ECU and implying they replaced the spark plugs, after stating that for $500 they OBVIOUSLY did the basic diagnostics which you failed to list in your "here's what i tried" section (which if they had done, $500 is a solid deal for labor). FWIW i know nothing of this shop, i've never been there never met anyone there, but if you actually run a small business i would be impressed; in my experience half the effort is dealing with customers who have zero grip on reality and no ability to be reasonable/logical.

2.7 melodrama belongs in the b5 s4 section. maybe two, three people in regionals here who could help you... and you already shit on jimmy and the only other person/shop we know you've tried to get help from... soooooo. good luck?

[highPSI-S4]

These are at idle misfires, any under load? have you tried loging the car? And assuming SAI/EGT are coded out your running some type of wide-band o2. Have you looked at that? Bosch Side Fires were the go to on STGIII 2.7 cars regarding spark plugs.

[V1nny]

These are at idle misfires, any under load? have you tried loging the car? And assuming SAI/EGT are coded out your running some type of wide-band o2. Have you looked at that? Bosch Side Fires were the go to on STGIII 2.7 cars regarding spark plugs.

I tried 3 or 4 different plugs including , NGK iridium and copper with different Briks and Bosch 3-electrode (JHM recomends them for stage 3) they do not need to be gaped, and NGK both iridium and copper, gaped to different gaps, none of these help. Most of the misfires are showing in the log under load, but at idle car does some strange things, like occasional hesitation and shaking, while running normal for a while.
Should I really try sidefires if none of the other made any difference?

Yes, Josh coded out both EGT and SAI. No wide band. Does ECU needs to be coded for wideband O2? Would wideband possibly fix misfires?

[V1nny]

if your focus was to get advice, then your response to my first post would have been "here are the logs" or "i will take logs ASAP and not waste everyone's life posting slander until i do"

not state they did nothing, after stating they did replace the ECU and implying they replaced the spark plugs, after stating that for $500 they OBVIOUSLY did the basic diagnostics which you failed to list in your "here's what i tried" section (which if they had done, $500 is a solid deal for labor). FWIW i know nothing of this shop, i've never been there never met anyone there, but if you actually run a small business i would be impressed; in my experience half the effort is dealing with customers who have zero grip on reality and no ability to be reasonable/logical.

2.7 melodrama belongs in the b5 s4 section. maybe two, three people in regionals here who could help you... and you already shit on jimmy and the only other person/shop we know you've tried to get help from... soooooo. good luck?

I have VCDS but my logging experience is limited. Would anyone locally able to help me to log?
and my sincere apologies for asking plebeian 2.7t questions in this elite section, would asked in B5 section, except I do not have a B5.

As for Jimmy, I have nothing but respect for both his mechanical abilities, and how he handled the screw up that happened to my air suspension which he had 0 experience with and only worked on it because it gave up literally in his driveway and car was not drivable or even towable, rubbing with all 4 wheels.

[Slow4]

I think it's your ECU or something related to the tune; you said tuner knew exactly what was going on but didn't care to acknowledge or change it.

Send it back to him and ask him to take off the tune, drive around and see if there's a difference.

[drumnjuny]

my sincere apologies for asking plebeian 2.7t questions in this elite section, would asked in B5 section, except I do not have a B5.

In this light, I sincerely hope you fix this problem soon. and I sincerely will be available for any help you may need logging. sincerely feel free to text me and i will answer with indisputable sincerity

[DieselElectric]

Need specifics on plugs gaps.

I run coppers at .019, any larger and it misses under load. So what "many gaps" did you try? I believe you have stronger coils, so it's probably a little more lenient.

Also, what's your AFR under load?

If you can't give specifics of what is happening to your car, we can't help you.

[V1nny]

Need specifics on plugs gaps.

I run coppers at .019, any larger and it misses under load. So what "many gaps" did you try? I believe you have stronger coils, so it's probably a little more lenient.

Also, what's your AFR under load?

If you can't give specifics of what is happening to your car, we can't help you.

I heard with red R8 coils people were ok with as large gaps as .028.

lowest I tried with NGK copper was .024. I did not see anything in VCDS for AFR, but just googled that it can be calculated from block 002 data. I will try to log it tomorrow and drop details here. My exhaust smells a little rich.

[DieselElectric]

Yea with the more modern coils you should be OK.

If your car isn't a wideband model (I doubt it was in 01, the later 2.7 allroads did get them), then the o2 readings are near worthless. You can get ballpark, but that's it.

I strongly suggest you install a wideband sensor. It's a huge diagnostic aid as well as a warning of unseen problems that can arise from daily use.

[V1nny]

engine seller from PA called me back today to tell that VIN is not available, so I won't be able to verify mileage. For now ordered new N75 and 4 bar FPR. Probably wasted another $150, but really not sure what else to do..

[drumnjuny]

diagnose the issue instead of throwing money at it

[DieselElectric]

That $150 would have been better put towards a wideband to give you useful insight into what's going on. Not being sarcastic.

I sure hope you aren't missing from going lean.

It's always a scary thing if the car runs great and suddenly develops problems. If the tune was the change before these misfires, then I could understand the speculation. However, since the misfires came out of nowhere, its a hardware issue.

You need to properly diagnose the vehicle. What are your fuel trims at idle and part throttle?

Wideband could take a lot of guesswork out of it, and assure you aren't taking another step towards melted pistons every time you try to test a guessed repair.

Tell me you aren't running stock fuel pump....

[drumnjuny]

That $150 would have been better put towards a wideband to give you useful insight into what's going on. Not being sarcastic.

I sure hope you aren't missing from going lean.

It's always a scary thing if the car runs great and suddenly develops problems. If the tune was the change before these misfires, then I could understand the speculation. However, since the misfires came out of nowhere, its a hardware issue.

You need to properly diagnose the vehicle. What are your fuel trims at idle and part throttle?

Wideband could take a lot of guesswork out of it, and assure you aren't taking another step towards melted pistons every time you try to test a guessed repair.

Tell me you aren't running stock fuel pump....

while he appreciates your help, you have a b5 s4 and he doesn't have a b5 so... nothing you could possibly say might help him. i wouldn't waste your time.

would asked in B5 section, except I do not have a B5.

[V1nny]

That $150 would have been better put towards a wideband to give you useful insight into what's going on. Not being sarcastic.

I sure hope you aren't missing from going lean.

It's always a scary thing if the car runs great and suddenly develops problems. If the tune was the change before these misfires, then I could understand the speculation. However, since the misfires came out of nowhere, its a hardware issue.

You need to properly diagnose the vehicle. What are your fuel trims at idle and part throttle?

Wideband could take a lot of guesswork out of it, and assure you aren't taking another step towards melted pistons every time you try to test a guessed repair.

Tell me you aren't running stock fuel pump....

I would definitely buy that, or whatever would hep me to fix misfires, but I do not which one to buy, I won't be able to install it unlike things that I bought, and I am not sure if ECU needs to be reprogrammed to take advantage of wideband sensors.

[V1nny]

while he appreciates your help, you have a b5 s4 and he doesn't have a b5 so... nothing you could possibly say might help him. i wouldn't waste your time.

could you please just leave for a while, so I can get some help here?

[Evilevo]

while he appreciates your help, you have a b5 s4 and he doesn't have a b5 so... nothing you could possibly say might help him. i wouldn't waste your time.

Are you serious Arjun? The ECU and 2.7T in the allroad is exactly the same as the B5 S4.



OP, do you have OEM coil packs or switched to the newer style?

Have you done a boost leak test? Charge pressure deviation code shows something up with boost and or boost control.

Have you tested to make sure your wastegates are working properly?

NGK copper plugs are all you need. That's all I ever ran on my 600whp S4.

[Slow4]

Tell me you aren't running stock fuel pump....

Hmmm, good point, what if it IS the fuel pump or a fuel related issue?

I still think it's a software issue within the tune.


Royale W/ Fromage

[Cgoon009]

What about:

Carbon build up?
Low fuel pressure/ bad pump
Bad Exahust sensor?
Clogged Cats?
SAI system?
Vacuum leak?
Throttle Body alignment?

[V1nny]

Changed coil packs twice, first time from original old style to newest 2.0 tfsi, then to red R8 coils.
fuel pump was changed from original to Walbro two years ago with stage 3.
Fuel filter was changed when I bought the car with 90K miles, change again?
Anyone who can locally help me to figure this out could ha any of these parts I changed for no reason.

[V1nny]

Carbon build up? 2.7t not known for having this issue
Low fuel pressure/ bad pump possibly, not sure how to check
Bad Exahust sensor? EGTs are coded out in ECU
Clogged Cats? 3" Downpipes from RAI
SAI system? Blocked off, coded out in ECU
Vacuum leak? possibly, not sure how to test
Throttle Body alignment? did some basic aliment, not sure if done correctly

[Slow4]

How many miles since the fuel filter change?

Run VAGCom, get logs before you do anything...honestly; without logs, you just throwing money at it.


Royale W/ Fromage

[Slow4]

Carbon build up? 2.7t not known for having this issue
Low fuel pressure/ bad pump possibly, not sure how to check
Bad Exahust sensor? EGTs are coded out in ECU
Clogged Cats? 3" Downpipes from RAI
SAI system? Blocked off, coded out in ECU
Vacuum leak? possibly, not sure how to test
Throttle Body alignment? id some basic aliment, not sure if done correctly

Bad/going bad fuel pump would make noises that isn't a humming nature or no noise at all.

Bad EGTs wouldn't cause a misfire.

Vacuum leaks can be diagnosed with simple DIY HD boost leak tester - every 2.7T owner should have one on standby

Get logs


Royale W/ Fromage

[drumnjuny]

Are you serious Arjun? The ECU and 2.7T in the allroad is exactly the same as the B5 S4.

i was trolling him b/c earlier he said he didn't post in the b5 s4 section because he doesn't have a b5 (i quoted him in my post lol)

[DieselElectric]

Egts can cause misses on the 2.7t. They make it dump as much fuel as possible and drown it out. But, coded out anyway.

I would log fuel trims, they should be <+-5%. I can't remember the block off the top of my head, but it's around here if you search.

[V1nny]

How many miles since the fuel filter change?

Run VAGCom, get logs before you do anything...honestly; without logs, you just throwing money at it.


Royale W/ Fromage

please please teach me how to "log everything" I will pay for it.. booze/parts/cash

[Slow4]

please please teach me how to "log everything" I will pay for it.. booze/parts/cash

Fine someone with a VCDS, connect to your OBDII, drive around and have VCDS record readings, export.



I don't have VCDS but there's a few dudes on here that might help you.


Royale W/ Fromage

[Evilevo]

please please teach me how to "log everything" I will pay for it.. booze/parts/cash

The boost pressure, positive deviation code speaks volumes. Misfires can be the result of another issue. You need to pressure test the car. I have a pressure tester that you can use.

Also, you said you have green top injectors. Those suck, lol. Which way are they facing? Are they facing the front or the back of the car or are they pointed out towards the fenders? IIRC, the green tops need to be pointed towards the fenders or they have misfire issues at idle. Bosch EV14 injectors are worlds better than the green tops though. I'd highly recommend you end up switching to them.

[V1nny]

not green top, never said that. Have Bosch green giants. totally different, except color
Smoke test was done on the car twice in the last month. It is still possible I have boost leak somewhere, and appreciate the offer, but have no slightest idea how to use that device.

[V1nny]

I have VCDS, but only know how to read reset codes. I tried to log, but it does not want to save files no matter what I do to it. Sort of logs, have empty file at the end, totally useless. Doing something wrong. That's why I am asking for help with logging. I been told 100 time to log everything. The importance of logging everything is by now very obvious to me. I wish I knew how to do it..

[DieselElectric]

At this point you just need to grab a bottle of Whiskey, and binge all night while absorbing as much information as you can. It's research time.

[Evilevo]

not green top, never said that. Have Bosch green giants. totally different, except color
Smoke test was done on the car twice in the last month. It is still possible I have boost leak somewhere, and appreciate the offer, but have no slightest idea how to use that device.

I believe it was green giants anyway. Just check their orientation.

Have you checked the wastegates? You would pull the vacuum lines off the N75 valve, and the line that goes to the Wastegates, blow into it. You should not be able to blow into it at all.

[V1nny]

I believe it was green giants anyway. Just check their orientation.

Have you checked the wastegates? You would pull the vacuum lines off the N75 valve, and the line that goes to the Wastegates, blow into it. You should not be able to blow into it at all.

Will check wastegates on friday, whe replacing N75. I am recalling now, when buying my rebuilt K04's guy in the shop told me that wategates currently set to 19 pounds and if I want to change it. I did not know what it means ( still have a pretty wague idea) and told them just leave it like this. Would it cause any issues?

[Evilevo]

Will check wastegates on friday, whe replacing N75. I am recalling now, when buying my rebuilt K04's guy in the shop told me that wategates currently set to 19 pounds and if I want to change it. I did not know what it means ( still have a pretty wague idea) and told them just leave it like this. Would it cause any issues?

Nope. Won't make a difference. Just means that in limp mode, ie WG open, the least amount of boost you can run is 19psi.