Auto Trans Experts - please chime in
 

My auto box has started to become a pain in the obvious. Its a mix of all sorts of nonsense - this is my A6.

Full history - I bought this car with 82K on it and it had Audi "Long Life" service which means basically the (dreaded) first owners only serviced it when the computer went "ding" and told them to do so. It has a full service history though based on this requirement from Audi themselves.

I have had the trans fluid changed at 82K and the garage got 2/3rds of it out which is pretty good apparently. They also did the re-learn step although I am wondering about this.

The box has never been happy though.

It "bangs" between gears when cold like a learner driver using a manual for the first time - come off the (house) drive accelerating gently and "bang" 1st-2nd and then "bang" 2nd-3rd.

When warm the up changes have tended to be smooth until recently where the change from 2nd to 3rd is very rough - the revs rise between the change and then the box catches up and switches into 3rd. 3rd to 4th seems OK as does 4-5 and 5-6. The same is true of down changes - 3-2 is very rough but 6-5, 5-4, 4-3 are quite OK.

Swapping from D to R also results in a "bang" every now and again too. If I pause from D - N - R then it is much smoother.

So any advice - is my GB OK and maybe the TC is Beggorah'd ? A reprogram from the garage, low fluid (how do I check ?). etc.

Ta.

EDIT - this is my first Auto as an owner.

Could be fluid. On the lifetime fill vw/audis, you basically fill till it overflows. The eurovan (T4) guys like to change the lifetime fluid every 40-50k miles. You really need to have a vag-com if you plan on keeping the car around for awhile.

My suggestions:
-1 fluid swap since you're already overtime to do so (with another relearn)
-2 still nothing, vag com
-3 shows nothing get the VB redone using the sonnex mods. Its a diy r&r, fairly skilled skill to mod. Just be careful with the solenoid wiring.

fyi, a "relearn" is just holding the pedal to the floor with the key on, engine off.

Is it a multitronic?

If so they are notorious for failing, there is an ecu inside the box itself

The multitronic pos cvt was a fwd trans, the quatto should be a 09l tip.

Its a Tipchronic - standard 6sp Auto.

Fluid has just been done at 82K, now on 85.

VAG-COM scanned a couple of weeks ago with nothing with the GB - a "lazy" glowplug seems to be the only mech fault.

What is the VB Redone ?

Thanks.

VB = valve body. There are modifications to flow and springs that help (sonnex mods).

Hmm. OK.

Just to be totally annoying the box has behaved perfectly for the past couple of days...

Sounds totally like fluid.

If the fluid is too low then the torque converter cannot fill up and it will be choking on air, a really bad way to transfer power from the engine to the gearbox.

http://www.youtube.com/watch?v=pTfipsejqS0

If the fluid is black in color then yeah, change it, and the trans filter.

Usually when transmissions go bad they make a big BANG which can be heard from inside of the car.

But I did have a Ford Auto trans which had a sensor inside it gone and it made it smash into 1st-2nd-3rd.

Seeing as that I was quoted $1,000 for a repair on that one I decided to get a reconditioned one for $650 fitted in shop, I ended up selling the car soon after.

Your options:
#1 Drive it up a hill, stop the car, put your foot on the brake and put the t-bar into neutral or park, then put it back into Drive and take off, if it doesn't want to engage or move forward while going up a hill then you definatley have a fluid level problem.

To top it up, make sure you've driven the car for 10-15 mins, drive it to the auto repair shop and buy the proper fluid for it, then drive it back home and park it on a flat surface, probably the road.

Pop the hood, pull the transmission dipstick out and rub it on the grass to clean it, feed it with two hands back into the transmission and pull it out again to check the fluid, if its on COLD or LOWER then put in about 100mL to 250mL of trans fluid and check the fluid again some other day.

Never EVER check transmission fluid when the car has been sitting for a while, always check it right after doing a short drive. If you check the trans fluid when the engine and trans are still cold then you will ALWAYS get a wrong reading on the dipstick of "cold or hot" or somewhere inbetween.

So if we warm up the engine and transmission, all of that fluid is gonna get sucked up into the parts of the gearbox and is now going to register zero on the same dipstick. a bad thing. It SHOULD be registering at least cold, or hot.

So its a good idea to make sure you check the stick when the transmission is warm, and NEVER when its bone cold.

My best guess is that the fluid level has been checked incorrectly during the last service.

Second option:
#2 Get it checked for free at an auto transmission place.

Third option:
#3 Take off the sump of the transmission and check the fluid for any metal shavings inside of it, replace the gasket and bolt it back up and refill it with sufficient fluid.

If you find metal shavings in the transmission sump then you've got problems.

@Yoyoyoda

Many thanks for that response - I had forgot about Eric, I watched his clutch video a few years ago - a DOH! on my part. I also watched his auto trans video just now too.

Firstly your tests - yep, it will pull away on a hill no problem at all. Even a really steep one like the one just under Edinburgh Castle. I have had instances where when I slip from D to R to get onto the drive (uphill) the revs have risen but no progress backwards. A quick slip to N and then back to R usually solves that one - has happened maybe 2-3 times so far.

The fluid and filter are fresh, I had them changed when I got the car at 80K miles. The garage that did it (I trust them) did explain that not all the fluid would be replaced as some does not come out which is what I found online about it. They changed the filter and cleaned out any metallic "fluff" (shavings) from the magnets in the sump - apparently from what I have read there will always be some :eek:

They also took time to do the "adaption" process although as they were short-handed that day and I think they might have rushed that element rather than keep me waiting - I was happy to wait but... I did wonder if that was the issue but I have run it myself to check. Again they did explain that to me rather than hide it which is what most garages would do.

Audi state the gearbox is sealed for life, but that is a myth like Audis never rust :rolleyes: Because of this I don't think there is a dipstick on the trans based on numerous Google and Google Image searches. There is a level check bolt and a filler bolt - the idea being you fill it up until the fluid pours out but this is hard to get to.

I will get the fluid level checked though this week and see what happens.

As I posted above though it has behaved more or less perfectly for the past week or so - smooth most of the time, the occasional 2-3 "lunge" where the revs rise in 2, pause at the same rate, and then suddenly drop as 3 comes in and the car lunges forward.

One other issue I have noticed is that sometimes when in D at a standstill there is a rumbling noise in time with the engine at idle so coming from the trans maybe. When I shift to N it goes away. It only happens sometimes though. The last time this happened I stopped somewhere for 10 mins and then restarted and it was fine again for the rest of the day. Engine mount maybe, exhaust perhaps vibrating against the floor at certain temps ? Who knows.

Enjoyed the brief blob of snow we had with AWD though :D

We have a similar scenario down here in AUS with a Ford Falcon EL model which came out with a sealed gearbox with the exact same method of refill as yours has. It is well renowned for failure and trouble.

The problem with the lack of a dipstick is that backyard mechanics will then shy away from replacing the transmission fluid on a regular basis, the exact problem which was meant to be solved by incorrectly filling an auto transmission actually just made the problem worse because then people just didn't bother paying for services. It backfired on the repairmen :P

96 EL Falcon gear change jerk - problem? - Ford - Automotive

This is the perfect place to start off with diagnosis.

Yeah could be that, have you done a thorough inspection of the transmission mounts? maybe something isn't bolted up properly.

If it were my car I would be underneath there with a flashlight checking out everything.

Failing those easy fixes...

It needs a proper inspection, solenoids can and do fail, it could also be a dirty connector somewhere on the outside of the transmission which is making an intermittent contact and is losing contact when you shift.

On my toyota a neutral selector sensor has a 20 pin connector where the silicone rubber seal around the inside of the connector had burst and let its silicone fluid run out down to the connector, clogging up the pins.

I disconnected the battery and cleaned out the connector with degreaser then made up another seal with black silicone from a tube.

http://i.imgur.com/MOe8123.jpg

Good luck :)

Here is a thought, maybe get the sump gasket checked too, if its leaking fluid then that will definatley cause that symptom.

Or try magic fluids. I can vouch for Lucas products.

http://www.youtube.com/watch?v=WjNbeInU6-4

I'll get the fluid level chacked on Monday at the place that does our work vehicles, and then get underneath when the bit of weather we are having here at the moment clears - my garage is full of MGB.

ps. I missed your post. New gasket was fitted at the same time, no leaks under the car either.

Also that falcon link is similar but opposite - the guy there is saying his is worse when warm, mine is worse when cold.

I'll start the process tomorrow.

OK - Booked in for the fluid to be checked Friday together with a few other issues.

For the past few days I removed the grill block (temps getting to 105 C) and also drove Hermann like a normal auto driver - i.e. no use of N when coasting.

Guess what ? Issues more or less went.

No snatchiness even when cold, 2nd-3rd is still "pausing" but much less than before and no jerking in other gears.

I even found Hermann behaving like an excited puppy on A-roads again - the flappy paddles are responsive (there is a Clarkson annoyingly long pause of about 0.5 seconds as usual) and changes using them are smooth again.

I have tapped that the gearbox seems like the gears are being worked by someone who is drunk and wearing boxing gloves but at least the boxing gloves are gone.

I'll still get the levels checked though, amongst a few other items...

That's great to hear, if your temps are higher in the transmission it can cause issues like slippage.

Transmission fluid if its not in the right temperature range can cause all sorts of issues not to mention a shorter life span.

I would suggest that if you want to keep the air dam that you install an external transmission cooler and put it in front of your a/c evaporator and radiator. Just be careful and get it properly installed with the right fittings, doing a half-assed job on your expensive vehicle with an auxiliary transmission cooler could end badly. When you use clamps and ordinary rubber hose on transmission coolers they can end up popping off.

I would also recommend that you get a temperature gauge and measure temps of your transmission housing just to be sure its that, a cheap infrared no contact thermometer will work just fine and let you check temps elsewhere too.

Either that or make up an aluminium cowling which will scoop up some cool air from the airstream below your car and let it push air onto the transmission.

Depending upon your current weather situation that could have been the issue all along, the front air dam.

I don't know about Audi's specifically, but many newer computer controlled automatics "learn" the way they get driven. If you always drive with your foot to the floor when passing people, the ECU will get in the habit of ramping up line pressure and holding your shift points longer when you are at WOT for example. It's also why weird things like a faulty mass air meter can make the transmission act up - the engine may not have a lot of load on it, but the signal the ECU is getting from the faulty meter is confusing it, so it won't apply the correct line pressure, shift points, etc for the given engine load/RPM. My genius tech friend explained it to me much better than that, but that's the "I drive a '90 Civic 5 speed" technical version of it. When he services a transmission in a vehicle that has had a hard life trying to get it to smarten up, after the fluid/filter change etc, he will disconnect the battery for a few minutes, then take the vehicle for a long test drive, taking it easy. The ECU has been reset by the battery disconnect, and for the first while of the test drive it's "learning" to shift/act normally again.

If driving your car "normally" seems to result in the transmission not acting up, it seems to me that the transmission had originally learned to operate normally, and perhaps your hypermiling techniques were confusing it? The same way a faulty sensor would cause it to act up, the ECU is looking for one set of learned parameters and is stumped with what it is actually receiving. For what it's worth, it's free to disconnect the battery, try it and then just take the car for a normal drive, see if it does anything weird. My advice is free so take it for what it's worth ha ha, good luck. :snail:

Edit: Adaptive transmissions, that's what they are called, now I remember. Here's some idea of what I was getting at http://www.thetruthaboutcars.com/200...transmissions/

Update today - my local specialist checked the fluid level for me (for free!) and noted it was at the right level and of good quality - at that point I said it had just been changed so that got a thumbs up.

They did a full on check of the rest of the car and noted a front suspension wear problem (which I knew about) and some software updates needed.

I've booked it back with them for the suspension and engine SW update (one of 3 needed, none are for the trans) next week. I planned to do these anyway and these guys seem quite good so a good time to do it. I have a few other issues to sort as well which they also detected without me telling them which is good - for me anyway. :thumbup:

I would get under the car myself but my drive is a steep slope :rolleyes: and this is Scotland which is bloody cold. I do have to remove the rear bumper tomorrow to fit a new parking sensor though. :eek:

I wondered about this too, however as part of the fluid change there is an "adaption procedure" which reprograms the box to adapt to new fluid - the garage did this twice and I've (tried do) do it myself.

Although thinking further maybe the car is adapting itself to it's first "caring owner". The DPOs (Dreaded Previous Owners - a classic MGB owners' term for normal people) seem to have accepted the idea of Audi long life service which means an oil change at 18K (if lucky) and no gearbox fluid change at all - as it is "sealed for life".

So maybe it is in a state of shock ?

:D Good good gooD :D

Poor thing, maybe give it some comfort by talking to it ? :thumbup:

Here is your problem:
Did you start the learning process when the car is on a hill? if so then that could cause some problems for the transmissions learning process..

I would suggest that you re-start the learning process and just park it on a flat surface until everything has settled down.

If its at all possible =D

Long time no update in this topic.

The box has been behaving better since redoing the adaption process but still has occasions where the changes seem quite harsh. Case in point this week during our round UK tour after 2-3 hours of cruising in 6th the changes down after that seemed very harsh for a while and then eased up. Changes up were as smooth as ever.

Been doing some reading and found this about changing fluid - I did mine at 81K. It could cause problems maybe :

I also wonder about the torque converter clutch - I wonder if when hot after a long cruise it doesn't disengage all that well so the trans remains locked for a split second in other gears. I also wonder if this clutch remains stuck on for a short while when starting from cold.

There are no error codes, no fluid leaks anywhere so not sure what else to try.

Again ideas welcome.