CVT "slip"

**hexc0de** · 05-29-2014 08:50 PM

I've started to notice that my CVT feels as if it's "slipping" under certain driving conditions. It seems to only happen when I'm going about 50 and start to climb a hill, and then apply more gas to maintain speed. About 1-2 seconds after applying the gas, the car will hesitate for a split-second, and I will get a small jerk that feels as if it's slipping into a gear. I know this doesn't really make sense because the CVT doesn't use traditional gears, but it's the way it feels. Note this is happening in "D" mode (I don't drive in S mode so I can save gas).

Has anyone else experienced this? Is this expected? I'm at about 68k miles and still under CPO warranty. I'm due for a transmission fluid change soon, but I'm trying to figure out if I should take it in to Audi before I get the fluid changed or not.

**oh10a4** · 05-29-2014 09:12 PM

Originally Posted by hexc0de

I've started to notice that my CVT feels as if it's "slipping" under certain driving conditions. It seems to only happen when I'm going about 50 and start to climb a hill, and then apply more gas to maintain speed. About 1-2 seconds after applying the gas, the car will hesitate for a split-second, and I will get a small jerk that feels as if it's slipping into a gear. I know this doesn't really make sense because the CVT doesn't use traditional gears, but it's the way it feels. Note this is happening in "D" mode (I don't drive in S mode so I can save gas).

Has anyone else experienced this? Is this expected? I'm at about 68k miles and still under CPO warranty. I'm due for a transmission fluid change soon, but I'm trying to figure out if I should take it in to Audi before I get the fluid changed or not.

Problem with the CVT in D ive found is that it too aggresively tries to keep your RPMs low and in my opinion puts you in gears too high for the situation. It also doesnt react as well to throttle response so it can hang into a high gear for longer, than it finally says okay fine you need more power and jumps down to a lower ratio lurching you forward.

This might not be your issue, but it sounds similar enough to some of my annoyances with the CVT. I've found that keeping it in S for any kind of stop and go traffics helps immensely, i only use D when cruising. If I need any type of power I keep in S or downshift via paddles.

**bdons** · 05-29-2014 09:44 PM

First of all the cvt doesn't have gears. It uses 2 conical shaped pulleys and belts to adjust rpms to the response of the pedal. It could be that the belt is slipping or becoming worn.

**oh10a4** · 05-29-2014 11:25 PM

Originally Posted by bdons

First of all the cvt doesn't have gears. It uses 2 conical shaped pulleys and belts to adjust rpms to the response of the pedal. It could be that the belt is slipping or becoming worn.

When I said "gear" i meant "gear ratio" which the CVT is constantly changing.

**ranchos** · 05-30-2014 11:15 AM

Well, Audi did program "gear points" into the CVT. So it'll fake shift sometimes.... it's ridiculous.

**hexc0de** · 05-30-2014 12:05 PM

It really bugs me. I drive 30 miles a day on mountain roads with many hills. I think I'm just gonna drive in S mode from now on.

**hexc0de** · 05-31-2014 08:01 PM

It's happening in S mode too. I'm going to take the car in to get checked out, I don't think this is normal. I would have noticed this 30k miles ago if it was by design.

**hexc0de** · 06-11-2014 05:24 PM

I had my transmission fluid changed today and the issue went away! Hope this helps anyone else who experiences this.

**hexc0de** · 09-18-2014 04:30 PM

Bringing this thread back. The issue came back and kept getting worse. I took the car into Audi today (under CPO warranty). They did some tests and I just got a call back saying the transmission is bad and they are going to replace it with a rebuilt tranny from Audi. He says this would cost $8k if I was out of warranty. The advisor also claims that Audi only has rebuilt transmissions, and that it isn't possible to get a new one for a 2009. Is this true?

Now I don't know if I want to keep this car... a transmission dying at 68k miles is absolutely ridiculous considering I baby this car.

**BettaJetta** · 09-19-2014 03:57 AM

How many miles do you have on the tranny? Also, in Germay, that is how they do things. They replace is with a rebuilt one. Not sure about stateside.

**hexc0de** · 09-19-2014 02:36 PM

I have 75k miles on the tranny but started noticing problems around 60k.

**CharlesP2009** · 03-27-2015 08:48 PM

My 2009 A4 is at 98,000 miles and the CVT is slipping more and more regularly. And it's always kicked like crazy if I try to rev above 2,200rpm or so. I really wish now I had gotten a Quattro car!

**yma4** · 03-27-2015 09:19 PM

Experienced the same thing over the past couple of years - intermittently under heavy acceleration. Took it to the dealer a couple of weeks ago and they performed a TSB software update to the tranny. All covered under CPO (which has now expired). Definitely much smoother now and no "slips" (yet).....

**booost** · 03-27-2015 09:26 PM

Same thing was happening on my old B6 cab 3.0 CVT, drove me nuts. Did a few things like TCM replacement and it would improve for a bit but always end up "slipping". I would only drive it in S mode or manual shifting because D was so unbearable. Hated that transmission and dumped the car as I really didn't need a vert in the northeast...

**CharlesP2009** · 03-27-2015 09:32 PM

Originally Posted by booost

Same thing was happening on my old B6 cab 3.0 CVT, drove me nuts. Did a few things like TCM replacement and it would improve for a bit but always end up "slipping". I would only drive it in S mode or manual shifting because D was so unbearable. Hated that transmission and dumped the car as I really didn't need a vert in the northeast...

I have been giving thought to jumping ship and getting a BMW 335i or 535i (I love turbocharged engines!) but those things seem to be more trouble even than Audi. Ugh, if only Lexus would make more interesting cars...

**Shimmy** · 03-27-2015 09:54 PM

what the hell is cvt? I thought we all bought audis for quattro

**CharlesP2009** · 03-27-2015 10:05 PM

Originally Posted by Shimmy

what the hell is cvt? I thought we all bought audis for quattro

I bought the CVT for the fuel economy and the promise of a smooth, comfortable drive in city traffic. I learned my lesson.

**booost** · 03-27-2015 10:08 PM

Originally Posted by Shimmy

what the hell is cvt? I thought we all bought audis for quattro

Trust me I'm with you lol I only picked it up as a summer top down cruiser because it was so cheap. Had some fun with it for sure..

**b6Hate4** · 03-28-2015 04:46 AM

CVT has always sucked and will always suck.

Crazy how few of us demand a manual transmission these days.

**mjt20mik** · 03-28-2015 07:30 AM

My first b6 was CVT. I learned my lesson from there and strictly kept it quattro since. I do miss the mileage sometimes. Getting 800km to a Tank on a 1.8T was awesome.

**spesho_boyz** · 03-29-2015 07:21 PM

i think i had this problem with my b8 as well. i took it to the dealer and they said it was my coil that is misfiring. So they replace all 4 coil and problem solve, surprise cuz i didnt know it will jerk like that.

**A4B8UAE** · 03-29-2015 09:38 PM

Do you guys think this "slip" could be attributed to the clutch getting worn?

**WngoA4** · 03-29-2015 09:40 PM

I'd always had the issue with my CVT on a hill. Sometimes it feels like I have a manual cause it rolls back a little. This been happening since day one.

**hexc0de** · 03-29-2015 09:49 PM

Been a while since I updated this thread. The rebuilt CVT tranny that Audi put in for me also ended up slipping within 500 miles of installation. I took it back to Audi and they confirmed that the transmission was bad (again!). Turns out that radiator coolant was leaking into the transmission cooler, contaminating the transmission fluid and leading to premature failure. Audi replaced the transmission again (with a brand new CVT this time) along with a new radiator/transmission cooler. A few months after I got what felt to be the same slippage, but Audi couldn't get it to throw a code. It ended up being a bad coil - replaced all the spark plugs and coils at once and I haven't had an issue since.

**Dave160** · 06-04-2015 05:30 AM

Sorry to bring this back from the dead but i am having the same issues as the OP. Brought the car to audi yesterday and they called me back later in the day and said nothing is wrong and there is nothing they could do

. It was skipping so badly a few times I had to get off the gas because it was so violent. Audi said they could not replicate the problem so there was nothing that they can "fix". $125 for them to tell me nothing is wrong when I know there is! Never going to buy another CVT again, Its the worst drivetrain i've ever driven. Period.

**Crucible35** · 06-04-2015 05:49 AM

From the description, I'm almost wondering whether the "Jerking"/hesitation some may be experiencing could be turbo lag coupled with the CVT. I've had a couple of CVTs as loaners and I found them to be very "abrupt" when accelerating especially up hills or around corners.

**Jacon** · 06-04-2015 07:16 AM

Originally Posted by Dave160

Sorry to bring this back from the dead but i am having the same issues as the OP. Brought the car to audi yesterday and they called me back later in the day and said nothing is wrong and there is nothing they could do

. It was skipping so badly a few times I had to get off the gas because it was so violent. Audi said they could not replicate the problem so there was nothing that they can "fix". $125 for them to tell me nothing is wrong when I know there is! Never going to buy another CVT again, Its the worst drivetrain i've ever driven. Period.

There's no permanent fix to the problem except to tear it apart and replace the internals (~$4000).

You can salvage some life from the trans by replacing the fluid and trans filter for a cheaper, but still hefty price (~$500). It will buy you some time, but the CVT is generally a ticking bomb. Some CVTs last for many years if driven softly, but most do not...

Sorry for your loss.

**bermudakid** · 06-04-2015 07:38 AM

Originally Posted by Dave160

Sorry to bring this back from the dead but i am having the same issues as the OP. Brought the car to audi yesterday and they called me back later in the day and said nothing is wrong and there is nothing they could do

. It was skipping so badly a few times I had to get off the gas because it was so violent. Audi said they could not replicate the problem so there was nothing that they can "fix". $125 for them to tell me nothing is wrong when I know there is! Never going to buy another CVT again, Its the worst drivetrain i've ever driven. Period.

When you are experiencing the problem stop by audi and have a Service tech go for a ride with you, not a rep because most of them don't know jack sh*t about the cars they write the invoice for. This way they can see it and feel it for themselves.

**hexc0de** · 06-04-2015 09:22 AM

I had the shop foreman go on a ride with me to show him the issue. He immediately thought it was a bad coil. I left the car with them and got a call later that day saying they got the car to throw a code related to the transmission. Audi then authorized a rebuilt replacement transmission. That one was ruined within 500 miles due to the coolant leak, and they authorized another one. Both times they were able to get the transmission to throw a "slip" code. Interesting thing is I never saw a CEL come on with the code, but they were still able to make it show up themselves (I assume by driving the piss out of it). I would replace the spark plugs and coils first to see if it truly is a transmission problem (the jerking feels almost identical between these two different issues). If it still exists, I'd say drive the car like you stole it so it gets worse and then give it to Audi again. Hope you are under warranty as they said tranmission replacement was around ~$8k.

**bermudakid** · 06-04-2015 09:25 AM

Worse case scenario if you don't like the car as much as you should trade it in asap and cut your loses, replacing a CVT out of pocket wouldn't be worth it.

**Jacon** · 06-04-2015 12:57 PM

An obvious slip condition would trigger a higher than normal revving of the engine before the transmission engages and starts moving. It would almost feel like a slipping clutch. Another symptom would be a rough launch of the car from 0-5mph; almost like you romped on the gas from a dead stop.

**forcefed7** · 06-05-2015 09:15 AM

After owning an Audi CVT, I absolutely cannot stress enough how important it is to change the trans fluid on a regular basis.
Like many of you, my girlfriend's CVT starting slipping. Then it progressed to rolling backwards on hills when brake pedal was released slightly. The final nail in the coffin was when sitting on level ground, at a stop sign or stop light, she would release the brake pedal and the car would not move forward. It would behave as if it was in neutral. Slight rpm increments would sometimes force it to engage, other times you literally just had to wait up to 30-45 seconds before the trans would "wake up" and engage.
Dangerous trans behavior all around and we're lucky she was never rear-ended or hit.

We had the trans rebuilt by what I consider to be the best trans shop in Charlotte NC. The owner removed her trans, called me and asked me to come down to see what the issue was.
First he showed me the clutches. This was an original trans with around 119kmi on it. Maybe a little more. The first forward clutch showed some noticeable wear, but not awful. The remaining forward clutches showed almost no wear. This explained some of the trans behavior below 30mph, where it felt like it was slipping a little. Above 50mph the trans felt absolutely normal.
Then he shows me the variators. Like someone pointed out, there are two variators that can modulate torque between engine and drive components. Our Audi had a chain that went around both planetary variators.
Here's where the real problem was. The valve body wasn't programmed correctly from Audi to properly modulate the torque between the variators, which in turn caused the chain and variators to wear prematurely.
Our variators were scarred from the chain so badly, they could not be repaired.
The shop owner had to bore out some of the valves on the body to address the hydraulic pressure issue that lead to the premature wearing of the variators and chain.
He used a set of used, but good variators from another CVT trans he had in the shop. Lastly he installed all new clutches and new OEM chain. The rest of the trans he re-used.
Put it all back together and it's been fine for the past 30-35,000 miles.
The trans fluid has been changed twice in those 35,000 miles and each time after, the trans runs and shifts like new again.

I cannot stress enough how important it is to get your CVT fluid changed. I would recommend every 15-20kmi (around once a year).
It may not save all Audi CVT failures, but I believe it will GREATLY extend the life of your Audi CVT trans, no matter what Audi says for fluid change intervals.

Remember, there's a reason there was a class action lawsuit against Audi for their CVT trans. Someone at Audi wasn't being honest about the CVT failure rate (likely caused by incorrect service intervals).