allenst

first let me ask, would the vcds pick up any/all transmission issues other than if the ATF were low ?
I scanned, saved then cleared DTC's.
The drive is still slow and low RPM with a slight, very slight vibration.
when coasting into stop needle hits 1000rpm then pops to 1200rpm before settling back to 750rpm.


any thoughts on 01--very much appreciated.

01-Engine -- Status: Malfunction 0010
02-Auto Trans -- Status: OK 0000

Address 01: Engine Labels: 077-910-560-BFM.lbl
Part No SW: 4E0 910 560 A HW: 4E0 907 560
Component: 4.2L V8/5V G 0070
Revision: 00000000 Serial number: AUX3Z0CN528780
Coding: 0007773
Shop #: WSC 02313 785 00200
VCID: 1F4DC484CEFD2AD9775-804A

6 Faults Found:
17985 - Right Engine Mount Solenoid Valve (N145)
P1577 - 004 - Open Circuit
17831 - Secondary Air Injection System; Bank 1
P1423 - 002 - Insufficient Flow - MIL ON
17819 - Secondary Air Injection System; Bank 2
P1411 - 002 - Insufficient Flow - MIL ON
17538 - Fuel Trim; Bank 2 (Mult)
P1130 - 001 - System too Lean - Intermittent
17536 - Fuel Trim; Bank 1 (Mult)
P1128 - 001 - System too Lean - Intermittent - MIL ON
18010 - Power Supply Terminal 30
P1602 - 002 - Voltage too Low - Intermittent
Readiness: 0000 0000

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 09E-927-156.lbl
Part No SW: 4E0 910 156 E HW: 09E 927 156 A
Component: AG6 09E 4,2L5V USA 0110
Revision: 00000001 Serial number: 0025539
Coding: 0000002
Shop #: WSC 02313 785 00200
VCID: 2447CB68E79B09012A7-8071

No fault code found.

EricVonHa

Save the codes into a text file, clear the codes, then drive it for a while.

There is no point speculating what issues exist without clearing the (potential) battery fault first. Cars that have had a dead battery or the battery has been disconnected and reconnected can set that code. Along for the ride are any other erroneous codes. Best to clear out the muck and see what returns.

Outside of the battery being dead/disconnected, the secondary air injection is suspect. Not sure what would cause the lean conditions on both banks other than dead/dying fuel pump or something related to the high pressure manifold electrics. Clear the codes and report back.

To answer the question on the trans, yes, the trans TCU can be scanned separately within VCDS. Looks like it is "ok" as shown by the header.

What you are seeing on the tach and feeling is probably the engagement of 1st gear on the downshift. Or, the symptom fallout from the lean conditions if they are real.

Clear codes and see what happens through the next set of warmup cycles.

MP4.2+6.0

You can keep analyzing, but I think your prior description as well as this one may be implicating torque converter lock up if you take it at face value. But before that, VCDS does not pick up even low fluid, except indirectly if something is acting up. Thus, if you haven't checked that yet, more arm chair review and speculation isn't the logical next step. Proceed to fluid level check per the ZF or Audi documentation, and alongside look for any evidence of leaking (since it has to go somewhere). Your description and codes are such it could even be some kind of vacuum leak or malfunction like in the secondary air injection system where yo do have specific codes. Erratic air fuel ratio could cause subtle idle fluctuation and some sense of drivetrain vibration. Thus, painful though finding the SAI issues can be, that should be remedied and eliminated as an issue too.

On VCDS, to be clear it is not a comprehensive/one stop tranny diagnostic tool, it did not pick up my W12 physical seal issue I found in disassembly, nor was it specific on whether my solenoids were up to snuff or had to do with the issue I was seeing (faulty 6-5 downshifts). For an "on off" solenoid like torque converter lock up, you can trust it as far as basic solenoid clicking, but that doesn't ensure the physical valve function is correct. Others of the solenoids are variable rather than fixed on-off, so even harder t know with those; many operations rely on a combination of two solenoids acting correctly together. As another VCDS indicator, on my C5 4.2 with the junk 5 speed I had many an issue with, it basically gave me codes that by board postings would suggest it was blown internally. Later it did blow suddenly and catastrophically, but early on it turned out after about 2-3 years of searching that it was a bad output sensor wire somewhere between the tranny and the TCU in the many wire harness. Not the sensor, but the single output wire connection. When I finally bypassed the bad conductor, it shifted correctly after a lot of weirdness, MAF replace, fluid changes, different TCU, etc.

Mister Bally

Standard automotive troubleshooting techniques are sometimes required.

allenst

I have a concrete driveway with not one spot on it. I don't think I have a leak but will check.
Is the only way to check ATF level is by fill cap ? til excess flows out ?

I did read an exact description of my issue on another forum.
Dealer diagnosed torque converter.
How costly is that job ?

I do have vaccum leaks.

I did have battery disconnected.
and this rpm, torque issue started right after that.
I even got a shock once from door handle after I reconnected

MP4.2+6.0

To be direct, I think you need to get out there and do the diagnostics, or pay someone to do it. These posts kind of go on and on and seem repetitive.

But to the point, categorically fix the SAI issue. Clear? seems like that has been around these posts a pretty long time if I remember some prior ones. It can overlap the idle feel you describe. Analyze it 8 ways from Sunday, but that's my call from past 4.2 specific experience. No, no idea what happened with your battery disconnect or weird shock. Anything from random static to an alternator issue to ? And, certainly I would take it for a spin, maybe run some Techron through it and fix known issues before anything drastic.

Torque converter. Again, we are going around and around. As I posted in the prior thread, how can you differentiate between the solenoid function that controls it and the torque converter being controlled? Because it worked for one other poster? It's premature at this stage anyway, pending a basic fluid check and straightening out vac. leaks. If you get to that, a torque converter requires a tranny pull, plus the cost of the converter. Look up the price of the converter--often rebuilt--plus maybe a grand or even $1500 for R&R. That could be like three grand?. If you are wrong and it was the solenoid/Mechatronics valve body, then it was all a waste of time and $, and you have to pull the Mechatronics (which can be done in the car). Advanced work typically done only by specialist types.

Leak; there is the second belly pan under it (at least on my W12), and the forward pan comes back far enough to cover some of it. Leak could be on pans--did you see anything back there when you did recent oil change? Can also burn off if it happens to hit exhaust. Could be a prior owner/mechanic didn't know how to check/fill it right either. Thus, if you pull the fill plug with motor off, well over a liter comes out. Oops, now it is low when operating. And no, no super secret procedure or extra port--from the fill port underneath, motor running and tranny warm not hot (40 degrees C). Car has to be level; I do it using either my sloped driveway with ramps or in my garage with front on ramps and rear jacked up to re level. To Mister Bally's reply, a basic fluid level check is standard very early diagnostic procedure any time a tranny isn't shifting right and feeling smooth.

allenst

I have the scan tool in my hands right now

Mister Bally

I guess you're all set then.

Sorta related but off topic; My late dad, who was a master carpenter, once told me: I've saved a lot of my money, I can afford to go and buy platinum brain surgery instruments. However, all I could do is set them down on a cloth and look at them because I sure as hell couldn't perform any brain surgery.