allenst

this issue seems to have come back with a new feel to it.

start car.
have brake depressed
stop at R just to see how it feels and a little (I mean littel) shake and "engage" feeling goes through my hands.
Hit N on way to D and N is fine.
from N to D is when I feel the "engage" feeling twice that of the R feeling.
like a "hard lock" or "grab" once I hit D.

I have no trans error codes yet.
and atf was topped off.

do some reading hear and there, this feeling seems to suggest torque converter or drivetrain issue ? I also have read that an engine mount issue could cause these noises ?

the only other thing I can mention as new is that while climbing more effort is needed on pedal and some 'clacking' sound when I first tough the gas.

JohnnyJ A6Q

Clacking as in pinging from the engine, how it the engine running while in gear with foot on brake at stop, what fuel are you using, also YES a bad engine mount could give you the sensation of delay as the play is taken up because the engine is shifting side to side depending which mount is bad.

MP4.2+6.0

Look at engine torque mount--near front of motor on U.S. passenger side and see if cracked/blown. Can probably sort of see from above w/ hood open and looking at just the right angles. Brown oil around/below it is a give away. Also main motor mounts if not torque mount--need to look underneath to see those better.

If tranny, next step to try to improve is fluid change. Look for blown mounts first.

allenst

engine runs fine while in gear with foot on brake
I do have an engine mount code, have had it for years, and have been told by many repair persons to 'not worry about it'

MP4.2+6.0

Mount code is solely electrical. Has nothing to do with hydraulic/torn mount/physical failures. Torque mount is also separate (third one) relative to two primary mounts and has no electrical connection/monitoring at all, at least on W12 or my prior 4.2 A6. You need to physically inspect.

allenst

So I inspected the passenger side mount from above.
Though I could not see physical damage I did notice an oil film, mostly in the seat (?) of the mount.
Question: is that engine oil or tranny oil , I am seeing ?
(I have never seen any fluid leaks of any type in all my years owning the car)

allenst

my result was 2100rpm
my next issue is to find the 'stall-speed' for my 4.2
so if I use this guide it would suggest tranny is NOT slipping.


Your car's transmission is having some problems, but you're not sure what's wrong. It's possible that your transmission is fine, but your torque converter needs to be replaced. You can diagnose problems with your torque converters on many older transmissions by conducting a stall-speed test. Here's how to test your torque converter:
Take the following precautions Check with your car or transmission manufacturer to make sure it's safe to run the test. Most newer transmissions, as well as some older ones, can actually be ruined by a stall-speed test. Don't run a stall-speed test for more than five seconds at a time. Don't run this test on vehicles that have traction control or anti-lock brake systems. On some electronically controlled transmissions, a stall-speed test will set off your check engine light.
Prepare your car Before testing your torque converter, make sure all your fluids are in good condition. Also, chock your wheels and set the parking brake. If your car doesn't have a tachometer, install one that can be seen from the driver's seat [source: ASE Test Prep].
Start your engine Press the brake pedal all the way to the floor and start your engine. Shift your transmission into drive. Don't let go of the brake.
Put the pedal to the metal While pressing on the brake pedal, press the accelerator to the floor for two to three seconds. Don't exceed five seconds, or you risk blowing out the transmission. The RPM the engine maxes out at is the stall speed.
Interpreting the stall-speed test result If the RPM reading is lower than the specifications for your particular torque converter and engine, it means the torque converter is failing and needs to be repaired or replaced. If the RPM reading is too high, then your transmission is slipping and you'll need to investigate the problem [source: ASE Test Prep].

MP4.2+6.0

Can't tell from internet distance. If blown, often a big visible crack around the circumference, and some significant brown oil stains in and coming down from the area--a hydraulic type oil. Often on a nearby surface like a support, bracket or frame rail.

Did you check the torque mount when you say looking at from above--way up by the front corner of the motor around/above the alternator area? Torque mount is only about half as big in diameter as the main mounts that are further back and lower on both sides.

allenst

the mount I visually inspected was the one right below/beside the front left corner of the engine right down near the bottom of air box. in line with the belt.

it had some brown oil like residue on it

allenst

rereading your location description, sounds like I inspected the torque mount as it was clearly visible from above just down below beside the belt and alternator.