Audi A6 saloon 3.0tdi quattro 272hp

[Yuri]

Hi to all. Havent been on the forum for ages,because only had BMW cars in the family. Couple weeks ago we purchased A6 2016 3.0tdi quattro. It was purchased from Audi dealership and was audi approved with 28000 on the clock.
I am more of the BMW person,but really like the car and pleasure to drive. Wife always wanted one so thought give it a go. Love the Matrix LED headlights,those are state of art and are brill. Its quite weird spec,because does not have electric powered seats,those manually adjusted,very strange,but not bothering us at all.

When looking for one i was very worried about the s tronic transmission and that is why we went ahead and got one with low mileage and with warranty. After driving it for 500 miles i started feeling that gearbox acts funny. When coming to a full stop,after couple seconds there is a jolt,limp forward,not nice feeling. Downshift 3 to 2 weird and can feel slight judder at times.
So car went in back to Audi yesterday and when technician called me after few hours,i been told that car needs new mechatronic unit and nox sensor. To be honest i was shocked,just could not believe what i heard.
Audi is going to pay for all repairs,so no problem there.

My question is it not unusual for mechatronic to fail at such low mileage? Do i need to push for new clutch kit same time when they doing mechatronic unit?
Did anyone had problems with their car at low mileage?

What about nox sensor? Why would that fail? Would it affect performance of the car? It pulls very well considering i own bmw 530d with 280hp and that pulls like train.

What do you think guys,should i return the car and ask for my money back?

[lynalldiscovery]

If they are fixing it no quibbles I am not sure you can reject it?

We replace loads of nox sensors on the trucks at work, always the same fault, signal plausible but out of range ie its on its way out.

[Yuri]

Hi. Thanks for reply. Yep,i do also think that it would be hard to reject it. Now i had second thought about it and it not a bad thing they going to fit new mech unit in,should last long time.

[Yuri]

Hi everybody. I thought i add another few thing on the list that broke on my 2016 66reg,a6 3.0tdi audi with now 29k on the clock.
So this week Thursday morning i started car to go to work and i feel that car shaking a bit,like miss fire. I thought thats me still asleep��. So Friday morning same time i am on my way to work and same shakey,miss firing start again,but this time i saw amber icon on my dash. It is like little engine and seems to mean emission controll fault.
Car drives ok,i think its a tad low on power,but never pushed it,just usuall drive to work feeling.
At 10 o'clock i give a call to Audi dealership where we got it from and explained what issue i have. Girl on the phone said that earliest they could see me is 2 weeks. I was not very happy and she found a spot in weeks time. So i said ok and put the phone down. After work i decided to pop in there myself and let the see the car and confirm its ok to drive,because girl on the phone said its ok,but better not and thats not good enough.
So went there and explained my problem and Audi managed to find spot then to plug it in. After about 45 mins of waiting tech came out and his manager came out and said that crankshaft pos.sensor is playing up and they would need car in to do proper diagnostic and repair. I said ok. Then tech came and said that also glow plugs. I said so in 3 weeks from us buying it it needs mechatronic unit,nox sensor,crankshaft sensor and glow plugs? Tech was shocked. I raised question about mileage being real or corrected. Tech women asked me to wait and went to get someone. It was shop manager and there was negotiation about next steps. We agreed on giving it one more chance,that Audi will repair it and if another issue comes up then i give car back and get my money back which i think is fairplus i like the car and then trying to find something else can be a pain. We came to Audi after owning Bmw,my wife wanted audi allways,so i thought i make her happy��.
So far Audi dealer been good and looked after me,gave courtesy cars,so we have wheels when car is in.
So lads,am i wrong thinking mileage could have been corrected? Although i been told its not possible in this car,but iknow it is possible.
Did anybody had problems like that or its me just being not lucky��? It feels i still smell of Bmw???
Sorry for a long write up.
Thank you.

[bluezie]

Anything software wise is possible with the correct knowledge and equipment!
The was a means of testing the mileage, and that is to compare the actual mileage in the instrument cluster, with a calculated mileage in the engine ECU. Any discrepancy more than a few percent means something has been fiddled with. Generally car clockers only wind back the displayed mileage.
Audi should also have a record of mileage on their database from every time the car has been in for service and repair - it should be obvious from these records if something doesn't add up.

29K and all these failures? Something doesn't add up, the 3.0TDI is now very reliable, and it also it couldn't have missed and S-tronic oil change to ruin the mechatronic....

[Yuri]

Hi. Records of service visits to audi add up,so cant see anything there,but it could have been clocked before service,because interval is 2 years or 20k i believe. From service history i have it only had servicing and no repairs. First service it had at 5k and second at 23k so its 18k between. Car done 18k in 1 year so lots of driving.
When i first been told that mechatronic needs changing i askeg technician who called why so early,why at this mileage what going on? He said that over the years he seen many cars with even lower mileage needing mechatronic replacement.
People say that gen2 s tronic gearbox is improved and faults were corrected,but does not seem like it,at least in my case.
I understand that sensors can break,but glow plugs?
Also usually mechatronic failure pulls clutches behind it and vice versa,but technician said that it is only internet forum rrumoors and not the case.
Anyway i will post on here how i get on.

[Yuri]

S tronic not due in for service for another 9k so would go in at 38. I know how importand is gearbox service and it can prolong its life dramaticly.
Does anybody know wheather Audi changes both filters when servicing s tronic? I know they change external filter,but about internal one in the sump?

[bluezie]

AFAIK, the sump filter is not changed by Audi, as it's actually a strainer, not a filter, so you would hope little or nothing ever ends up in it, as it's there to catch large chunks of debris. The side filter catches fine particles, i.e. mainly clutch linings, and the even finer particles are held in suspension in the oil until the oil change, although when I changed my oil, I only got 4.5 Litres of the 7 Litre capacity to drain out, so the new oil was significantly contaminated with old oil.

[A8Cruiser]

The thing I have noticed with auto gearbox drivers, is that many people do not STOP before they change gear. I don’t why people do that. They are not manuals.

I always stop - as in stationery - before changing gear. Irrelevant of where I am or holding up traffic.


I wonder if the previous owner abused the box?
I suppose it is also possible that the NOx sensor issue might have changed all manner of engine settings?

[Yuri]

Hi. I think its very important to fully stop before changing gear on auto transmission.
I managed to have a look at clutch adaptations/bite points and clutches K1 and K2 looks as new. K1 is 2.7 and 6.8 and K2 is 2.4 and 6.5. So unless those have been replaced not at audi,because no service records show it,then i think it was not abused,just not lucky i think.

[Yuri]

Hi everyone. A bit of update on my a6.
Car went in for mechatronic,nox sensor,cylinder 5 glow plug and crankshaft position sensor replacement at Audi dealership last week Friday. I picked car up yesterday and been told that all is sorted. Car drives better,gear shifts much quicker and feels more powerfull. So i was happy untill i started car this morning to go to work and what do i see? Well lumpy idle for few seconds and emission control light on the dash.
I finished work and went to Audi to ask what the hell is going on with the car. They quickly plugged diagnostic and it came back with cylinder 5 glow plug. When i asked why didnt they change it they said that tech was thinking that glow plug fault ws because of nox sensor:zx11:. Unbelieveble:))))) Just couldnt belive it.
Also i complained about odd vibration when wheels are at full or almost full lock and starting to drive. They said that its because of wheel size plus the tyres are really good and grip really well. What a nonsense. After they did scan car i took technician.for a test run to show him vibration i complained about. Done it few times,well every time at near full lock at the begining of movement. Tech admited that indeed there is vibration coming from midle of the car.
All in i said that i would like to return the car,as its just no right and i dont trust this car no longer.
Will be waiting to hear from them now.
Really like the car,but too much problems with it.
Was it abused by previous owner? Why is it doing this?
Its very clean looking car. Matrix led headlights are amazing and trully are a state of art technology,but not reliable at this stage.

[bluezie]

It's a quattro, and they all do the vibration thing at full lock, especially on a hill, or if booting it. It's the Torsen centre diff-lock starting to lock up.
I've owned 3 quattros, and driven a few others, and every single one has done it. The only time they don't vibrate is a gentle pull away on reasonably flat ground, and the problem can be exacerbated by having very worn tyres on the front, and new on the rear, as this increases the differential speeds of the front and rear axles.

[A8Cruiser]

Agreed on the quattro vibration. All of my quattros have done this at various points. Only when turning out of a junction on a hill.

the tech should know this also. Check the trye depths etc.

[Yuri]

Hi. I read about that vibration. Mine does it even at idle,when in gear just let my foot off brake pedal and does it in reverse too. I know that its normal to some extent,but i think that in my car its bit too much. Tech was trying to say that this sound is not a diff but wheels are jumping.:D All tyres brand new bridgestones all 4 are same on 18 inch alloys.
Dont know if its true or not,but oil change in the front diff helps to sort this vibration. I know a guy back in Russia and his mate ownes VAG group independent garage and he says that when vubration.appears its time to change oil in the diff. Can confirm its true or false though.

What about statement that nox sensor could affect glow plug? Is that at all possible?

[Yuri]

Mine vibrates at any ground.

[bluezie]

What about statement that nox sensor could affect glow plug? Is that at all possible?

On the face of it it seems totally crazy! But you haven't posted the exact faults with the items. Do you have the full engine diagnostic scan, or even just the complete fault codes including their descriptive text? That may show why they came to that conclusion, eg if the codes were showing a wiring fault, they may have concluded it was a common to both items fault.
When a scan produces multiple sensor failures, 99.9% of the time it's not the sensors, but the common wiring, I did say in a previous post that something's not right to produce this number of failures at a very low mileage- but a broken or chafed common wire, or corroded plug easily could.

[bluezie]

BTW, a dead glow pug won't make the car start or run lumpy, or reduce its power. A TDI will start instantly without any glow plugs, unless the temperature is well bellow zero. Glow plugs these days are used to lower the warm up emissions, and are switched on for a long time after start up. There's something else going on here other than a dead glow plug, I'm leaning towards wiring.

[Yuri]

Well it runs lumpy first start of the day,but only for few seconds then back to normal. My bmw e61 530d has bad glow plugs and it behaves same from cold.
Fault code states cyl.5 glow plug activation. Emissions control light is on the dash too.

[bluezie]

Have you got the actual fault code/s, the above doesn't mean a lot.

[Yuri]

Will have it a bit later. Have vag com now so will scan it myself and see what codes i have. Will post on here so you knowledgeble guys could have a look at this and shed some light on it.

[bluezie]

Can you post a total vehicle scan please? Sometime odd stuff happens in other modules, just need to rule that out. Ross-Tech won't answer any questions without a full scan for this reason - a classic example, is a faulty wheel speed sensor will light up the dashboard like a Christmas tree, and log fault codes in loads of different modules!
Obviously cut out personal details from the scan like reg. no. and VIN no.

Have you any scans form when this first happened, with the other faults?

[Yuri]

Hi. My vag com is russian made. Its exact same Ross Tech just in Russian language so will write all codes it comes up with after total scan.

[Yuri]

Anyway scanned car and found 2 fault codes. One is in the engine controle module P0675 00 [237] cylinder 5 glow plug electric circuit fault
Second fault code is in Module 5F, MMI unit,fault code is B1564 01[009]. Funny why it explains fault as mass air meter 1. Air mass flow too high. Strange.

Scanner i am using is genuine bit of kit that a lot of indy garages who work with VAG group cars use. Its same as Ross Tech with all features and you can do everything that a Ross Tech can. It is regestered and can be updated and is for unlimited vin's.

Would be interesting to see it tested by somebody who knows and owns real ross tech scanner to see if my bit of kit does the job.

[bluezie]

I don't understand this, the first code seems to be a generic OBD-II code, not a Audi specific code, but that only shows there is a fault somewhere from the control module and the glow plug inclusive. The second one makes no sense whatsoever. The MMI should never report an engine specific code, especially as the engine isn't reporting it as well!
I suspect your scan tool isn't working properly, or something is being badly lost in translation.

[Yuri]

Hi. Worked out mmi code,its something to do with antenna,but ecerything works as it should.

Glow plug fault code is correct though,isnt it?

[bluezie]

Glow plug circuit fault code is plausible, but it doesn't say what is faulty, could be the glow plug, wiring or controller.