Understanding Audi A4/ A6 CVT transmission problems

[Krystal Car Part Imports]

Guys,

A lot of people ask me about Audi A4 transmissions with the CVT. They have problems. I have one with a 7 speed for sale at $15,000 with control unit and shifter,but that is not why I am writing.

It is clear to me, that quite a number of mechanics are Dodo heads when it comes to understanding euro cars, especially VAG cars.

Recently, a chap called me, he was getting a jerking whenever he pressed the accelerator hard in drive. sometimes it would come and sometimes it would go. His mechanic quickly concluded that his transmission was at fault.

How the f$%^ does he know that? he obviously isn't a very smart mechanic.

First tell tale sign of a transmission problem is not a shuddering. Rather the gears will begin to hold, and not shift to a higher ratio. Another sign is slipping or no engagement in reverse gear.

Chap's shuddering problem was caused by IMPROPER OR WORN SPARK PLUGS
1.8T 20 valve engines use either NGK BKR6 or BKR 7 spark plugs depending on the level of boost. BKR5 spark plugs WILL cause shuddering of the transmission.

Other transmission problems may be caused by :
- Bad multifunction switch (tells the transmission what gear you have selected on the shifter)
- Bad MAF sensor
- Someone removed the ECU and attempted to turn the ignition ( will cause a reverse color effect in instruments)
- Fault in harness wiring
- Faulty ignition coils
- Worn out CVT fluid
- Car was parked in a garage for a very long time.
- Faulty transmission speed sensor (s)
-Engine overheating

Unfortunately some early B6 6-speed CVT transmissions do experience hard problems such as:

- Damaged Transmission ECU caused by lack of CVT fluid maintenance.
- Damaged clutch packs caused by improper CVT fluid maintenance.

It is key to note that the Transmission ECU in a CVT Audi is located inside of the transmission.

In both cases of genuine transmission problems, or transmission problems related to faults in engine electronic components, your 'P-R-N-D' in the instruments will begin to show reverse colour when problems are severe ( instead of black background red letters, you will get red background black letters)
To correct this, one must use an Scan Tool with the correct protocols, and clear all the fault codes related to transmission. Understand, that some transmission fault codes are NOT related to the transmission being at fault, but a low signal from a component in the engine from which the transmission ECU must receive a signal for optimal operation.

To properly maintain an Audi CVT transmission one MUST
- Replace transmission fluid and filter every 40,000 miles or the equivalent in kilometres. This is more frequent than the manufacturer suggests but it is necessary in our climate. They need frequent fluid changes, especially in this country where we have chronic traffic jams.
- Keep your engine in good working order.
- Get a good mechanic: one that works or worked, or understand the cars well. There are a few around, PM me and I can suggest two are three I know.

Please know that Audi transmissions and older Passat transmissions have NO dipstick! The only way to check the level is to use a scan-tool. If you want to service the transmission on your own, I can write about that later. But only by request.

Finally, Use high quality CVT fluid. The transmission takes about 5-6 quarts of fluid. Febi and Pentosin are great brands, but EXPENSIVE. Vaico is a cheaper alternative and the same quality. You can get that from Autobahn TT. There is no magic in CVT fluid. I have used PEAK Synthetic CVT ( chain type) fluid in a B7 CVT transmission with absolutely NO problems or issues so far (about nine months ago) however CVT fluid MUST be approved for use in CHAIN DRIVE CVT's. if you are not sure, call the manufacturers' toll free number and ask. If you use Skype toll free numbers to the USA are exactly that- FREE

One last thing: If you ever meet a fat man named Jason and his friend Glenn, you must avoid them. Jason is ok-ish, but he ain't no mechanic really. Do your best to particularly AVOID Glenn. Glenn is a liar and a very EVIL person. Don't let him touch any car you own. he knows nothing and he can only help you lose your money.

[Pointman-IA]

Nice write up.

Just the other day I was telling someone that with the Renaults, when you change the transmission fluid, the car is to be hooked up with the scan tool and have the counter reset.
There is no dipstick to check the level as well.

[Krystal Car Part Imports]

Interesting....
I sincerely believe that most transmission failure in European cars is due to improper maintenance of the automatic transmissions. Broken down into 4 areas:

1. Infrequency of fluid changes ( taking climate into consideration)
2. Use improper transmission fluid
3. Lack of diagnostic service and support.
4. General ignorance of Trini mechanics who fail to understand that their first tool is the internet.

A lot of Peugeots have transmission failures as well. 206/ 307's and some older models. Interesting to note is that the 206/307 transmissions do NOT have transmission coolers, nor can one be installed. Therefore very frequent oil changes are necessary

[Krystal Car Part Imports]

I also have this post in the general tech talk. please post there as well.

[Pointman-IA]

Pug's AL4 and Renault's DP0 tranny are almost the same.

[Allergic2BunnyEars]

Nice stuff here. I skipped out on a used A4 because of transmission horror stories. Audi seemed to have an issue with respect to transmission control unit failures within the gearbox separate from the issues of improper maintenance.

Thoughts on why VAG specifies no transmission fluid changes in some trannies "for life" even in hot climates? By the way where is Autobahn TT located?

[Porro]

Excellent thread. OP is obviously very knowledgeable.

One point on the 206 AL4. There is a fitting that allows the engine coolant to be used to cool the ATF.

[Krystal Car Part Imports]

Excellent thread. OP is obviously very knowledgeable.

One point on the 206 AL4. There is a fitting that allows the engine coolant to be used to cool the ATF.

OK.

In my experience however, this cooling is not enough, and the transmission fluid is rapidly deteriorated by the heat generated inside the transmission. Its the second time I have ever seen pitch black transmission fluid. The first was with a high mileage corolla.

[Krystal Car Part Imports]

Nice stuff here. I skipped out on a used A4 because of transmission horror stories. Audi seemed to have an issue with respect to transmission control unit failures within the gearbox separate from the issues of improper maintenance.

Thoughts on why VAG specifies no transmission fluid changes in some trannies "for life" even in hot climates? By the way where is Autobahn TT located?

The Audi CVT transmission of itself is a well designed well built unit, however the whole idea of a 'lifetime' tranmsission fluid is very misleading and nonsensical. No transmission fluid is 'lifetime' not even Mobil 1 synthetic. Fluid changes are the key to its longevity. Several A4 and A6 owners have the original 6 speed CVT with no problems.

Autobahm TT is located on Mucarapo Road past the secondary school.. i think they have a website, you can get their number.

[kg494EJ-1]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

[EcoTune Trinidad]

AutobahnTT # 2232020

[Mazdout]

They're on mucurapo road on the left, not to far after the Jamaat compound - can't remember the mall name.

Gr8 write up

[purple_heart77]

Thanks for taking the time for this write up, wish I had know this years ago.
I had similar experience with NOT changing transmission oil for 10 + years in a Bora, I say no more what happened. Did a transmission oil change at 40K miles on my Passat, hoping to not repeat the issues suffered with the Bora.

[Team Loco]

And that was one well maintained bora u had

[Pointman-IA]

And that was one well maintained bora u had

Hahahahahaha....well yes.

[Krystal Car Part Imports]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

Who knows, sometimes maybe a CVT oil change may very well solve the problem permanently without having to tear down the transmission. Get advice from a good independent mechanic.

[Krystal Car Part Imports]

Oh, BTW, i found an american source where I can get transmission kits for bora, audi and VW. everything except whole valve bodies. So, hit me up if u interested to know more

[StefanH2]

very good write up here.. thanks for the info.

[Russellgold]

Inside..
Nice info for future reference

[Porro]

Is it cobra transmissions?

[kg494EJ-1]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

Who knows, sometimes maybe a CVT oil change may very well solve the problem permanently without having to tear down the transmission. Get advice from a good independent mechanic.

Was on a little hiatus will be going to AutobahnTT to check it out after the Carnival Season but the times I've driven the car since the error shows most of the time and when it doesn't I have no reverse,when I put it into reverse the light show begins and reverse is back, other than that it drives quite normal, luckily I have other vehicles but to those that asked I'm keeping the A4 hell may even throw in a gearbox if push comes to shove really enjoy driving that german bugger.

[Porro]

Have you ever had a diagnostic performed since the transmission started to give trouble?

[kg494EJ-1]

Have you ever had a diagnostic performed since the transmission started to give trouble?

Got it done by SS, however they did not tell me the exact code, just stated there was no com to the TCU/TCM hence the reason I'm looking for a reliable second opinion, I'm not exactly a fan of wasting money or having things done twice. Thinking of investing in my own vagcom system because I've already started playing around with the vehicle.

[Krystal Car Part Imports]

Have you ever had a diagnostic performed since the transmission started to give trouble?

Got it done by SS, however they did not tell me the exact code, just stated there was no com to the TCU/TCM hence the reason I'm looking for a reliable second opinion, I'm not exactly a fan of wasting money or having things done twice. Thinking of investing in my own vagcom system because I've already started playing around with the vehicle.

If southern Sales tells u they cant get communication to the TCU, a second opinion will only reveal the same. The guys at the dealership know what they doing

[Krystal Car Part Imports]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

Who knows, sometimes maybe a CVT oil change may very well solve the problem permanently without having to tear down the transmission. Get advice from a good independent mechanic.

Was on a little hiatus will be going to AutobahnTT to check it out after the Carnival Season but the times I've driven the car since the error shows most of the time and when it doesn't I have no reverse,when I put it into reverse the light show begins and reverse is back, other than that it drives quite normal, luckily I have other vehicles but to those that asked I'm keeping the A4 hell may even throw in a gearbox if push comes to shove really enjoy driving that german bugger.

ge
Yo, I have a 7-speed CVT transmission with TCU sitting here in my garage. Good working order. Got it from a wreck. Call me if you looking to replace and save some time and hassles. 478-0106

[Porro]

Kg

Check your pm

[sweeks]

Invaluable info here .... Excellent thread

[shimon]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

Hey did you ever sort out your tranny and at what cost did you finally settled at. Thanks.

[kg494EJ-1]

WoW this post seems to be sign Friday afternoon, leaving work my B7 A4 refused to go into reverse, then the PRND started flashing, immediately my heart sank (dreaded unit failure) switched off and restarted it came back to normal, on my way home in traffic it stalled as if I failed to clutch in time and the lights were back.
Saturday, the lights remained blinking but the car drives as normal,same for Sunday and Monday. Went to Audi in POS and before they ran a scan I got a 21k verbal quote for repair 12+ for the part and remainder for labour.

I am going to have to get it done but I'm looking around because of that display at Audi(SS), the receptionist just giggled and rattled of a cost before the vehicle even got into the yard. First real problem in 6+ years of ownership and 100K+ on the odometer. But I must admit the vehicle remains parked up sometimes for 2weeks+ or even more.

Thanks for this post.

Hey did you ever sort out your tranny and at what cost did you finally settled at. Thanks.

Haven't done it yet I had the car scheduled to do some work previously headliner started sagging a while back and some cosmetic changes so that's currently being done, once completed I'll sort it out but I was informed by SS I'll be given a warranty on the repair so that may be the route I'll take.

[shimon]

Ok cool bro goodluck