Audi A4 2003 Frontrak B6 CVT Multitronic Oil/Fluid change/flush
08-22-2014, 02:29 PM
#51
AudiWorld Member
The selector lever fault is interesting. When a sensor is intermittently faulty, you would suspect some mechanical failure which puts the sensor on the limit of its function, e.g., dodgy switch contacts, or a leaky pressure or vacuum device. When a sensor has no wearing parts, such as a magnetic pickup or an optical transducer, then I would be inclined to look for something, such as dirt, or misalignment, which would cause the sensor to fail, but not consistently. In the case of the auto box the sensors are hall effect, nothing to wear except the levers that carry the magnets, so the only other cause of intermittent ( as distinct from total) failing would be something like muck or metal or a mechanical displacement. A lifetime repairing tells me, and you I suspect, that most intermittent faults can be resolved by a good cleaning. This holds true for cars, domestic appliances, oil boilers, mobile phones, TV sets, agricultural machinery, telecoms equipment, computers, and anything else I've had the pleasure of dismantling and fixing in the last 45 years. So I'd say you are on the money too, a careful removal of the TCM, examine, clean, flush and refill. Fwiw, there are fluid additive detergents which can be used to give it an extra scour before refilling, I'll have a look for the link.
09-11-2014, 01:30 AM
#52
AudiWorld Member
Got to do the first drain a few days ago . Gave the cars a very short start when it had drained and got a bit more out . About 5 litres .
Very little sludge in it . Small gritty metalic bit on the drain plug .3 pin heads in size
Let the fluid settle for 1/2 an hour and then drained it into my DIY filter setup.
Very little sediment , only 3 bits and only one was metalic gritty , other was a grain of sand and a soft bit the size of a grain of sand which disintegrated between my fingers.
Fluid was quite clean and not smelly at all so I filtered through and refilled the transmission with the before mentioned brilliant pump . About 30 strokes all up.
I'll do this 2 more times and then use new fluid.
No change to transmission fault so I'm now convinced this is similar metalic grit attached to the magnetic fingers of the selector lever giving an implausible digital signal ( see the .pdf of the transmission for the codes)
May try to access the case and TCM on the next drain.
Very little sludge in it . Small gritty metalic bit on the drain plug .3 pin heads in size
Let the fluid settle for 1/2 an hour and then drained it into my DIY filter setup.
Very little sediment , only 3 bits and only one was metalic gritty , other was a grain of sand and a soft bit the size of a grain of sand which disintegrated between my fingers.
Fluid was quite clean and not smelly at all so I filtered through and refilled the transmission with the before mentioned brilliant pump . About 30 strokes all up.
I'll do this 2 more times and then use new fluid.
No change to transmission fault so I'm now convinced this is similar metalic grit attached to the magnetic fingers of the selector lever giving an implausible digital signal ( see the .pdf of the transmission for the codes)
May try to access the case and TCM on the next drain.
09-12-2014, 07:25 AM
#53
AudiWorld Member
So far so good. All set to do my change tomorrow. KKL cable no use, mine is a 2007, all CAN, no K-line so just got a HEX/CAN cable plus software, (16€) works perfectly, already noted some minor historical faults, nothing of importance. Reset my service counter, at last! Tomorrow I'll drain and refill, monitoring transmission temperature. I might leave the adaptation for the moment. I'll do engine oil and filer while its up, its due, and I'll also change the rear brake pads, using the VCDS and cable to wind back the electric parking brake. As an aside, I actually got to use the torque app and elm bluetooth OBD plug to read and clear a fault, a "mixture too lean" which turned on the MIL lamp. This was caused by not pushing the dipstick home fully when topping up the oil (a condition of TFSI engines), causing air to be drawn into the crankcase, through the breather valve and into the manifold, weakening the idle mixture past the point where the ECU could compensate. So Torque has paid for itself. I shudder to think what this might cost at a dealer, probably 100€ just to connect the computer, then who knows how many hours looking for the complex reason when the simple one is staring you in the face. The difference I suppose is that I knew I had just topped up the oil, so I checked that first. I had also bought some cheap gas on the road, then I read about certain discount garages thinning out petrol with kerosene (much less tax), which can cause havoc to direct injection engines. I thought the worst at first until I copped the dipstick. I'm the dipstick I think.
09-15-2014, 01:26 AM
#54
AudiWorld Member
All done, it was straightforward enough. I got about 4 litres on the drain, didn't fancy turning over the engine to get more out. It was very clean anyway, insofar as there was not 'bits' or sludge, but it was a darker brown than the fresh stuff and had a bit of an odour. I pumped in 4L before over flow, then another half litre after running, the ran it until it warmed to 30 degrees on VCDS, stopped and opened the drain and about 100mL ran out, so I'd say its just right. When topping up you could see the old fluid coming out with the overflow of the new, definitely darker and slightly cloudier. If it was really bad, it would be worth another 4-5 litres to do a second flush, but in my case its a routine fluid change at 180,000Km. My pump arrangement was a breeze, I used an old 10 litre garden sprayer, took off the spray bar and removed the little filter from the bottom of the inlet tube, just gave it a dozen quick pumps to pressurise and sit back and watch the level drop. When it overflowed, just released the pressure with the valve on top. A doddle. Done my engine oil and filter while up, and then done the rear brakes. First time using VCDS, took a little while to figure the electric parking brake rewind routine, but easy in the end. My only near disaster with the fluid change was when I put a Torx instead of a 10 mm hex into the top up plug, had a brain freeze I think. I knew it was a 10mm allen key but it didn't fit at first and looking up it looked so like a Torx. I almost sheared all the corners of the ALUMINIUM plug, but there was enough left for the hex key when I finished swearing and reset my head. It opened, so panic over. I'd love to have something better than a pokey trolley Jack, getting all four wheels off the ground high enough to work and keep the car level takes a good few cycles of jack, bloc jack etc.
The off the ground adaptation was a non runner, in my version it wont allow you to cycle through the ratios with the manual tiptronic, it detects the back wheels are stationary and just refuses to rev past idle. It's spot on this morning, pulling well, no judder or slip, not that I had any, so I'll leave well enough alone. VCDS is the biz, it should come with the car.
The off the ground adaptation was a non runner, in my version it wont allow you to cycle through the ratios with the manual tiptronic, it detects the back wheels are stationary and just refuses to rev past idle. It's spot on this morning, pulling well, no judder or slip, not that I had any, so I'll leave well enough alone. VCDS is the biz, it should come with the car.
Last edited by deezell; 09-15-2014 at 02:26 AM.
09-15-2014, 02:22 AM
#55
AudiWorld Member
Sounds good .Lot to digest in those posts .Who would have thought the dipstick allowing air in would affect the mixture ! I noticed that I had a suck in of air when I loosened the transmission drain plug initially. Not a lot but noticeable . I would have thought air pressure in the gearbox would be vented in some fashion or air would have leaked past the oil seals somewhere so this intrigued me
Your spray pump idea is a good one too. I would have ten of those around the farm but didn't think of that . I have decided to back up my driveway which is sloped up to the garage then put car ramps under front wheels and drive forward until I get it level this time . Your right the trolley jacks and stands are a pain. Got mine up with a brick under each wheel last time but it still needs 4 jackups as it won't drive straight up on the bricks and halving it with some pavers first works but then if you just run a little bit too far the bricks spring up and hit the body .Grrr
Your spray pump idea is a good one too. I would have ten of those around the farm but didn't think of that . I have decided to back up my driveway which is sloped up to the garage then put car ramps under front wheels and drive forward until I get it level this time . Your right the trolley jacks and stands are a pain. Got mine up with a brick under each wheel last time but it still needs 4 jackups as it won't drive straight up on the bricks and halving it with some pavers first works but then if you just run a little bit too far the bricks spring up and hit the body .Grrr
Last edited by tytower; 09-15-2014 at 02:29 AM.
09-18-2014, 07:46 PM
#56
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Shudder at low RPM in D, not in multitronic--Help
I had a guy that works at an european auto repair shop tell me that when they do the flush it usually makes the slipping worse. Now i'm not sure wether or not to do the flush. my b6 slips at low rpm in automatic, but not currently when I shift using multitronic after 2k rpm.
09-22-2014, 01:00 AM
#57
AudiWorld Member
mrsapril now thats a coincidence .
On your car i would hazard a guess.
The clutch on your car is inside the gearbox. It is normally a six plate clutch and the Transmission Control Module (TCM) decides when to engage it by oil pressure and when to select neutral or park (Pressure off) and a separate clutch is engaged to put it in reverse.
That's how I understand it at this stage. When they repair the gearboxes it seems they change the clutch plate pack from 6 plates to 7 and that takes the operational ability up by about a third !
So we have an oil bathed clutch in effect I think . Definitely the pressure though is controlled by the TCM. After changing the oil the mechanics do an adaptation process with a laptop and Vag-Com program which sets some pressure figures in the box and I think that's probably to do with the clutches.
If you are in overdrive (6th) and gently press the accelerator as you go itno a climb you will get slippage of the clutch if it is worn. Try to avoid this by using the tiptronic function to change back a gear or two. Alternatively give the accelerator a sharp push for a second to force it to bring the revs up and consequently the gear ratio down . Relatively from 6 th to 4th .
This is what I have with mine . Let me know please if this rings true with yours when you try it .
Again try to avoid that slippage when you feel it as it means some wear from the faces of the clutch plates each time it happens and they are getting worse each time until they eventually let go and you will have no drive whatever.
Don't panic . The condition is manageable as long as you know what to look out for and a new gearbox should be a long way off .I think a 7pack clutch swap would fix it up if thats all you have noticed . Do you get the flashing indicator ?
If so see my previous posts to get a laptop connected to read the error codes yourself.
I redid the adaptation procedure as I concluded it might help . I did not know how long ago it might have been done . I did not own the vehicle . That resetting made it better I think but did not eliminate slippage which for me feels like it is slipping say 1 revolution and catching then for a half second then slipping a bit again etc.
On your car i would hazard a guess.
The clutch on your car is inside the gearbox. It is normally a six plate clutch and the Transmission Control Module (TCM) decides when to engage it by oil pressure and when to select neutral or park (Pressure off) and a separate clutch is engaged to put it in reverse.
That's how I understand it at this stage. When they repair the gearboxes it seems they change the clutch plate pack from 6 plates to 7 and that takes the operational ability up by about a third !
So we have an oil bathed clutch in effect I think . Definitely the pressure though is controlled by the TCM. After changing the oil the mechanics do an adaptation process with a laptop and Vag-Com program which sets some pressure figures in the box and I think that's probably to do with the clutches.
If you are in overdrive (6th) and gently press the accelerator as you go itno a climb you will get slippage of the clutch if it is worn. Try to avoid this by using the tiptronic function to change back a gear or two. Alternatively give the accelerator a sharp push for a second to force it to bring the revs up and consequently the gear ratio down . Relatively from 6 th to 4th .
This is what I have with mine . Let me know please if this rings true with yours when you try it .
Again try to avoid that slippage when you feel it as it means some wear from the faces of the clutch plates each time it happens and they are getting worse each time until they eventually let go and you will have no drive whatever.
Don't panic . The condition is manageable as long as you know what to look out for and a new gearbox should be a long way off .I think a 7pack clutch swap would fix it up if thats all you have noticed . Do you get the flashing indicator ?
If so see my previous posts to get a laptop connected to read the error codes yourself.
I redid the adaptation procedure as I concluded it might help . I did not know how long ago it might have been done . I did not own the vehicle . That resetting made it better I think but did not eliminate slippage which for me feels like it is slipping say 1 revolution and catching then for a half second then slipping a bit again etc.
Last edited by tytower; 09-22-2014 at 01:00 PM.
09-22-2014, 10:26 PM
#58
AudiWorld Member
Originally Posted by mrsapril
In Drive, my car shudders and chugs at low RPM
I can get out of my car to open a gate with the car all operating normally and by the time I reach the gate I hear the revs go up to 1000 .When I get back the display has started flashing for the transmission. When I put my foot on the brake the revs drop to 700 as normal and drives normally but the car is erratic when I come to a stop and jerks about.
I think this is happening because the computer reads the gear position and brake pedal amongst many other things on a regular basis. When it gets a bad reading on the gear selector shaft it puts it into some sort of failsafe mode to get you home I suppose .
I have concluded then that I have two issues with my car
1./ A gear selector sensor problem and
2./ A slipping /worn forward drive clutch plate pack.
three actually because sometimes at the same gate it just refuses to start . I have to lock it and walk away for a couple of minutes and then come back ,unlock it and it starts roughly if I hold the accellerator pedal down a bit then it comes back to normal in a couple of secs . I think it reckons I did not pay enough money for it when I bought it and it thinks I must have stolen it ! General consensus here is that it is a fuel rich issue as there is no flashing immobiliser light on the dashboard a and if it were the immobiliser it would start and then stop
EDIT It came to pass that the problem got worse on the refusal to start. It would start cold but not hot. Flooded and i had to leave it for at least half an hour. The 4 wire temp sender had gone out on one side . Dash read fine but the computer got no reading so it assumed the worse and set it for -20C. Consequenty here in the tropics it immediately flooded . Cost to fix ? $3 AUD with a new sensor from china . Got 3 just in case .Dificult to install but can be done . not had the problem since.
Edit 2....23/10/19 The $3 temp sensor is still going strong . No repeat ever of cold starting problem.
Last edited by tytower; 10-22-2019 at 02:28 PM.
01-29-2015, 08:11 PM
#59
I did a fluid flush on a 2003 AUDI A4 with a CVT transmission and it now shifts much better than before. Turns out its not that bad to do, at least not as bad some people make it seem on other threads/forums.The transmission was replaced at 55k with an updated 7 disc trans. Now at 106k it was starting to jerk again, especially when the car accelerates from a standstill. Overall the trans worked poorly and was getting progressively worse. I read somewhere that a "double flush" of the fluid really restores the performance of the CVT, the "double flush" requires refilling the trans with new fluid driving it around for a little to circulate it throughout the trans and then once again draining it and refilling with all new fluid. (Waste of fluid but cheaper than a new trans) The reason for this is the CVT holds 7+ quarts but only 4ish quarts drains out so doing the double flush is one way of making sure more fluid gets replaced with new fluid.
To do this you will need OEM Audi approved CVT fluid/oil, buy this from your dealer, around $20 a quart, or order online from ECS tuning. Audi has a special VAS-5162 tool that costs $200 for filling fluid in the trans. However it is unnecessary in my experience, I bought a nifty fluid transfer pump from harbor freight for $5 and it did the job just fine! You will need the special 3357 tool, this is a triple square m16 tamper proof bit that is necessary for the drain plug. You can buy this online from several sites or ebay for around $30. I bought mine from a local Snap-On for $40. You will need a 10mm Allen bit for the fill/overfill plug. Also a vag-com is necessary to check the fluid level. Because the fill plug is on the bottom of the trans it gets tricky to check the fluid level so the vag com is necessary.
As a disclaimer Im not responsible if you ruin your trans and if it is completely toast a simple trans fluid probably wont fix it. When I did this my CVT worked fine overall it was just jerky. If your careful though there shouldn't be any problems. To start I jacked up the car a little, some say it is important to have the car flat but I think as along as the CVT is filled and drained while the car is lifted at the same angle it wont matter. The bottom of trans has two plugs. The black tamper proof plug is the drain plug and is opened with the 3357 tool. The silver allen plug is for filling and checking the fluid level.
-Drain the fluid, (almost exactly 4 quarts drained from the my trans.) The fluid will come out a darker color than the new fluid and if you look closely you will see small metal flakes in the oil and this is ultimately what cause the trans to shift poorly and eventually fail if fluid isn't replaced. The dirty metal filled fluid gets clogged in all the mechanisms of the trans and it starts to shift progressively worse until it finally fails. Reinstall the black drain plug.
-Now crack open the silver drain plug, a little overfill fluid should drain out. The hose diameter of the Habor Freight Fluid transfer pump just happens to be the perfect diameter for the trans. The hose is slightly smaller in diameter but I wrapped some electrical tape around the hose a couple inches down and then shoved it into the fill plug. It should fit tight enough so that you can fill the fluid without leaking everywhere. The pump is fast, several pumps and a quart bottle will be fully drained into the trans. I filled just slightly more than I drained to be safe ( just over 4 quarts in my case, might vary for you based on how level your car is). You will drain the overfill anyway when checking the level with the vag-com. Once again make sure the car is jacked at the same angle when filling and draining to make sure you don't under or overfill! Also notice the jackstands so you don't die!
- Fluid should be filled and the fill plug closed for now. I lowered the car but placed some 2x4's under the wheels so the fill plug would still be accessible. To check the fluid level with the vag-com go into the Auto Trans controller on the vcds software, then go to measuring blocks, enter 10 for the display group and you will see the trans fluid temp in the third window. The car will have to have to idle to warm the trans fluid, revving it too 2.5k rpm will warm up the fluid faster. Let the fluid warm up to 35 degrees Celsius and then open the fill plug you should have some fluid run out of the fill plug keep it running till cvt fluid temp reaches 40 C, fluid should keep dripping out the fill plug, if it does fluid level should be good. Close the fill plug before the temp goes past 40c. Your CVT oil change is done, if you want to do the double flush, which I recommend repeat all the steps again with new fluid. I recommend doing this every 20k miles to keep the CVT operating right, with good clean fluid these transmissions should run for a long time and operate smoothly.
To do this you will need OEM Audi approved CVT fluid/oil, buy this from your dealer, around $20 a quart, or order online from ECS tuning. Audi has a special VAS-5162 tool that costs $200 for filling fluid in the trans. However it is unnecessary in my experience, I bought a nifty fluid transfer pump from harbor freight for $5 and it did the job just fine! You will need the special 3357 tool, this is a triple square m16 tamper proof bit that is necessary for the drain plug. You can buy this online from several sites or ebay for around $30. I bought mine from a local Snap-On for $40. You will need a 10mm Allen bit for the fill/overfill plug. Also a vag-com is necessary to check the fluid level. Because the fill plug is on the bottom of the trans it gets tricky to check the fluid level so the vag com is necessary.
As a disclaimer Im not responsible if you ruin your trans and if it is completely toast a simple trans fluid probably wont fix it. When I did this my CVT worked fine overall it was just jerky. If your careful though there shouldn't be any problems. To start I jacked up the car a little, some say it is important to have the car flat but I think as along as the CVT is filled and drained while the car is lifted at the same angle it wont matter. The bottom of trans has two plugs. The black tamper proof plug is the drain plug and is opened with the 3357 tool. The silver allen plug is for filling and checking the fluid level.
-Drain the fluid, (almost exactly 4 quarts drained from the my trans.) The fluid will come out a darker color than the new fluid and if you look closely you will see small metal flakes in the oil and this is ultimately what cause the trans to shift poorly and eventually fail if fluid isn't replaced. The dirty metal filled fluid gets clogged in all the mechanisms of the trans and it starts to shift progressively worse until it finally fails. Reinstall the black drain plug.
-Now crack open the silver drain plug, a little overfill fluid should drain out. The hose diameter of the Habor Freight Fluid transfer pump just happens to be the perfect diameter for the trans. The hose is slightly smaller in diameter but I wrapped some electrical tape around the hose a couple inches down and then shoved it into the fill plug. It should fit tight enough so that you can fill the fluid without leaking everywhere. The pump is fast, several pumps and a quart bottle will be fully drained into the trans. I filled just slightly more than I drained to be safe ( just over 4 quarts in my case, might vary for you based on how level your car is). You will drain the overfill anyway when checking the level with the vag-com. Once again make sure the car is jacked at the same angle when filling and draining to make sure you don't under or overfill! Also notice the jackstands so you don't die!
- Fluid should be filled and the fill plug closed for now. I lowered the car but placed some 2x4's under the wheels so the fill plug would still be accessible. To check the fluid level with the vag-com go into the Auto Trans controller on the vcds software, then go to measuring blocks, enter 10 for the display group and you will see the trans fluid temp in the third window. The car will have to have to idle to warm the trans fluid, revving it too 2.5k rpm will warm up the fluid faster. Let the fluid warm up to 35 degrees Celsius and then open the fill plug you should have some fluid run out of the fill plug keep it running till cvt fluid temp reaches 40 C, fluid should keep dripping out the fill plug, if it does fluid level should be good. Close the fill plug before the temp goes past 40c. Your CVT oil change is done, if you want to do the double flush, which I recommend repeat all the steps again with new fluid. I recommend doing this every 20k miles to keep the CVT operating right, with good clean fluid these transmissions should run for a long time and operate smoothly.
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tytower (10-22-2019)
02-02-2015, 12:45 AM
#60
AudiWorld Member
Good to bump the original thread up. I'd still maintain the car should be level, the fluid will overflow at different level if the box is tilted. Also, 40 bucks for the tripleX key is stiff, bought one for a quarter that.
Last edited by deezell; 02-02-2015 at 01:27 AM.