Ah, that reminds me Justin - while talking about the Y-pipe… another place that I noticed was the oil separator adapter that essentially feeds into the back of the lower intake. There is an o-ring in there that I found to be leaking when I replaced my intake. I opted to just use RTV to seal it and call it a day.
Thanks for that info Justin! I will look at that in a few weeks when I resume troubleshooting.
That oil separator adapter oring caused me issues a few times… I was able to find a replacement oring for that connection.
I have two thoughts in my head to what my issues are (I’ve said them before)
clogged cats - but need to check measuring blocks ect for that (but the exhaust sounds different too, like it’s being restricted)
hole in diaphram in oil separator. I unplugged the separator from the valve covers and still have quite a bit of vacuum in the valve covers.
I wish I could dedicate time to this right now, but I have to get my other car (95 Mercedes E320 Wagon) ready for a roadtrip/show in Minneapolis (430 miles away) If there’s any other members going to Eurowerks let me know.
keep us posted. I would caution you to be careful before you come to the condlusion that your cats are plugged while this is an issue on the 5.2 motors its a rare one and you generally see a cat code before there is any real restriction. So I again would urge you to be careful on thinking its a cat issue.
Crank case pressure is one thing but you want to see crank case vacuum. so again I would caution getting too concerned just yet with that. Obviously too much is a concern but you are suposed to have quite a bit of crank case vacuum thats what stops your car from leaking oil out every seal.
Looks like something going on with the O2 sensors and a list of misfires now. (I had a chuckle at the speed of which the second O2 sensor warning came at… oopsie)
Noticing that misfires are happening off idle and under load… I don’t get a flashing check engine light until I’m off the gas. Also noticed that they are at different times at different cylinders.
So to recap… carbon clean has been done, new fuel filter, IM spacers installed, JHM Tune, new plugs, new valve cover gaskets, new coils, new oil/air separator, new suction jet, checked all around intake with starting fluid/brake clean and finally did a smoke test for vacuum leaks. None found. Still have lots of vacuum under oil cap.
I’m stumped.
I plan to cut out the cats anyhow in the next few months, and now replace the O2 sensors. And will likely pull the injectors to get cleaned and upgrade the bolts from the JHM Kit. I don’t see anyone else saying anything, but when I torqued the intake down as described in sequence at 11ft lbs… some of the bolts stripped. So I’d like to put better cap screws in.
The battery had died from the car sitting so some of these codes are related to that.
Self-Diagnosis Log
Wednesday,20,September,2017,22:05:58:15433
Page 2
VIN: WAUGN74F87N168471 License Plate: CHRIS S6
Address 01: Engine Labels: Redir Fail!
Part No SW: 4F1 910 552 A HW: 4F1 907 552
Component: 5.2L JHM/V1 OCT9 ª0040
Revision: 59H14— Serial number:
Coding: 01050009190F0160
Shop #: WSC 02335 758 00200
VCID: 224BD8C3FDF3B856BC-8076
7 Faults Found:
000086 - Oxygen (Lambda) Sensor B2 S2: Heating Circuit
P0056 - 004 - Malfunction / Open Circuit - MIL ON
Freeze Frame:
Fault Status: 11100100
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 152151 km
Time Indication: 0
Date: 2017.05.22
Time: 17:44:01
well this is bad. 008756 - Oxygen (Lambda) Sensor B2 S1 and the car is missfireing on that side of the motor. and it has a accurence rate of more then just once.
If I read the logs correctly, looks like you’re getting the following from the passenger side: 1, 3, and 4. And then from the driver’s side: 7, 8, 9, and 10. From my understanding the only cylinder that is related to your O2 codes (B2 S1, B2, S2) is cylinder #4 as it shares that bank of O2s with cylinder #5. You might be right in that some kind of harsh chemical caused the pre and post cat O2s to fail. One alternative idea I have is that they might share a common relay or wiring that is causing the heaters to malfunction. Does anyone know if there’s a common relay behind the knee panel below the steering wheel?
Also, I noticed you said a few of your IM bolts stripped (Ugh!) but you don’t notice any vacuum leaks when you smoke tested the system. Did you try smoke testing the system while hot after a normal drive?
Sorry if you’ve already done some of the above stuff… just trying to throw stuff at the wall in hopes that it helps cause I know I’d be ready to drive the car off a cliff if I was in your shoes!
Yeah the last 2 months have been a wringer… haven’t been able to think straight with a death in the family, so troubleshooting has taken a back seat (I have a few other cars so this isn’t my daily)
B2 is driver side, so the misfires in cyl 7,8,9,10 follow those O2 sensors.
Also worth noting, Carbon clean was done in May. And the first batch of misfires occurred right after. Then later misfires occurred at varying times on varying cylinders. (1 and 7 misfires on Aug 18; 4 on july 15; 8 on june 16) I’m not sure if that how I should look at this that these were the times those cylinders were misfiring or if that was just the first time it happened (i’m sure justin can elaborate) Car ran great for a few months and I did have a few times where it ran sluggish… then one day in August (after the 18th) it just always ran sluggish.
As for the stripped bolts, the smoke test showed no leaks at the manifold, so for now I can state that there are no vacuum leaks that leak externally (I still feel like there is far too much vacuum coming from the oil cap, but I’ll deal with that oil/air separator issue another time) And did the smoke tests while hot as well as you had mentioned… I was getting more misfires while driving (see logs) and on decel so I figured it might be something happening while the engine was hot.
They also stripped while doing the final torque value, but still annoying because I want to pull the intake to do the injectors in the next few months.
TBH my plan this winter was to pull the engine, gut or remove the cats, replace 02s, replace injectors and paint the car. I do the work myself and have access to a lift in November so that’s likely when I will do the work. I did just want to share what was happening here so that in the case that someone else is in this predicament, there is a path and solution.
Not everyone is going to be thrilled or ok with yanking the engine, but it doesn’t really bother me.
Sorry to hear about your loss! Family and friends first without a doubt!
Regarding the O2s, I was under the impression that the layout was like this (At least in North America):
Back of car
Passenger Side (ECU 1) | Driver's Side (ECU 2)
O2 Bank 2 5 | 10 O2 Bank 4
O2 Bank 2 4 | 9 O2 Bank 4
|
O2 Bank 1 3 | 8 O2 Bank 3
O2 Bank 1 2 | 7 O2 Bank 3
O2 Bank 1 1 | 6 O2 Bank 3
Front of Car
Have I been looking at the layout all wrong this entire time? (I hope not!)
Wow… very interesting. I was using this PDF from AW as my guide when coming up with the diagram I made up above. I noticed that it lists banks 1 thru 4.
My logic was that when you pull up measuring blocks 32 and 33 to look at the long term and short term fuel trims, VCDS displays
To make things more complicated we have 2 ECUs, and from the same PDF that you posted, the next page in that document lists which ECU collects data from which O2s. It looks like ECU1 collects output from the passenger side O2 sensors and then ECU2 collects output from the driver’s side O2 sensors.
So when you access ECU2, measuring blocks 32 and 33 essentially should look like:
Measuring block 36 on ECU1 will give you the O2 voltages for B1S2 and B2S2. Measuring block 36 on ECU2 should then display output from B3S2 and B4S2.
Sorry for the long-winded post. Just showing my thought process behind the above diagram. I want to make sure that I have this correct in my head, especially if I’m going to keep this car for many more years! Am I way off the mark here?
My bad guys… fixing an error in my post above (doesn’t look like I have edit capabilities for my posts) The second “code” block should be as noted below:
In your diagram you have two B1S1 sensors and that is obviously completly incorrect.
Here is how it works you have it correct here
Back of car
Passenger Side (ECU 1) | Driver's Side (ECU 2)
O2 Bank 2 5 | 10 O2 Bank 4
O2 Bank 2 4 | 9 O2 Bank 4
|
O2 Bank 1 3 | 8 O2 Bank 3
O2 Bank 1 2 | 7 O2 Bank 3
O2 Bank 1 1 | 6 O2 Bank 3
Front of Car
The 02 sensors follow the pattern as you have listed here.
B1 = bank 1 S1= sensor 1 in that bank … Then you would have B1= bank 1 =S2 sensor 2 on that bank (post cat)
Since the V10 is broken into two banks per side you have two banks per side The other sensor on that same passenger side would be
B2 = same side of the motor as B1 but the second part of the system S1 = Senor 1 on the second bank
Then you have bank 2 of the total motor or the driver side of the motor. But so as to not confuse Audi techs Audi broke bank 2 or the driver side into new banks noted as B3 and B4
So on the driver side of the motor known as B2= bank two or driver side… Since the term B2 is already being use on the passenger side of the motor on ECU 1 Audi used B3 and B4
On the driver side you have
B3= bank 3 S1= sensor 1 in that bank… then you would have B3=bank 3 S2= sensor 2 on that bank
B4= bank 4 S1= sensor 1 in that bank … Then you would have B4=bank 4 S2= sensor 2 on that bank
So you have
Passenger side B1 and B2
Driver side B3 and B4
The primary 02 on each of these banks will be under S1 and the sensor post cat will be S2
Dont confuse the universal side refrence with the 02 refrence.
Audi calls the passenger side of the motor bank 1 and calls the driver side bank 2. This is for the over all motor but when you talk about the 02s its broken down into 4 banks.
Now to help make this even more confusing as you mentioned you have 2 ecus so the bank 1 ecu on older software versions flashed into the 5.2 motors broke the data into only two banks per ECU and not 4 banks total. So old documentation might still reflect this. But this was obviously hard to dignose so you will notice that all car fax data shows audi had a manditory ECU update to help make a change to 4 total banks other than B1 and B2 per ECU.
Back of car
Passenger Side (ECU 1) | Driver's Side (ECU 2)
O2 Bank 2 5 | 10 O2 Bank 4
O2 Bank 2 4 | 9 O2 Bank 4
|
O2 Bank 1 3 | 8 O2 Bank 3
O2 Bank 1 2 | 7 O2 Bank 3
O2 Bank 1 1 | 6 O2 Bank 3
Front of Car
MOTOR ONLY
B1 is Passenger Side;
B2 is Driver’s Side (LHD)
O2 SENSORs
Passenger side B1 and B2
Driver Side B3 and B4