Leetch

I have a 2006 A4 2.0T with the CVt transmission. Recently I had my engine fully rebuilt but when I got the car back a strange problem occurs every now and then.

I first notice it when I pulled up to a stop light, the car jerked briefly then the transmission lights lit up on my screen and kept flashing. No other problems (i.e. no slipping, etc) and the car still ran fine. I turned the car off and back on and the lights stayed flashing. After letting the car sit at work for an hour, I turned it back on and the lights weren't on anymore.

Later that day, I went our for lunch. While sitting at a stop light I decided to trun the car off since the exhaust was still slightly smoking from the rebuild (I didn't want to offend anyone around me). When I turned the car on, I stepped on the gas and the lights came on again. This time while I was driving, I dropped it into neutral then back into drive but it wouldn't go into gear and the engine light as well as the transmission gears all lit up. I pulled over and turned the car off and back on. The lights stayed on but the car went into gear fine.

The next morning when I started up, the lights were off again. I brought it back to the mechanic and he thought it was just due to the connector being loose so he re-did the connection to the tranny. He ran it for a few days and the engine light never came back on but the transmission did it to him again where it wouldn't go into gear.

There are no codes to speak of letting us know what the issue is and a transmission person said he would have to drop the tranny and pull it apart to figure it out. I'd rather not go down that road if I don't have to.

Any thoughts on what it might be? I have no clue how the CVT transmissions work but from old school thinking it sounds like the automatic clutch isn't engaging for some reason.

The car did sit around for about a year after the engine blew and was being rebuilt so all kinds of problems could pop up. Any thoughts on what might be causing the transmission problem would be appreciated.

Dolamite

You should get a vag-com and scan the car first to have some trouble codes to work off of. I would change the auxillary in line filter that's outside and change the CVT fluid first if both haven't been done in a while. It may be that your transmission control module is going bad or the transmission needs to be rebuilt.

The 2006 I believe had problems with an excessive amount of CVT failures. There may have been a recall, but I doubt one without warranty. They upgraded the number of clutch plates and reflashed the TCU. There is a company down south that does CVT rebuilding, but it's not going to be cheap. The TCU repair can be done, but the tranny needs to be opened up.

Leetch

Finally got a code from the transmission problem. It's P0706. From what I can tell it's related to a sensor. Is this hard to change or is it something I need a shop to take care fo for me. Are there any other possible causes of this code?

Dolamite

I'm hoping it is just a sensor. There might be an issue with the TCU(transmission control unit). A cvt experienced shop should be used on this. http://http://www.fixeuro.com/Transm...top=true#Video keep us posted. Give these guys a call with questions.

Find out if there's anything that can be done by Audi as far as warranty and assistance for covering costs. Dealer first then Audi of America if you can't get anywhere. You may have to start by getting it diagnosed from them.

Prospeeder

It probably needs a new TCU like they all do. be sure too your changing the CVT fluid every 30k miles or you will just be wearing it out and destroy it. As it wears out and fills full of metal it all sticks to the magnets on speed sensors and can weaken their signal.

Leetch

Thanks all - It might be a few weeks before I truly find out the issue. I have to take my car back to the mechanic who rebuilt my engine because it's still smoking and burning oil after 500 miles (not much but enough see every now and then but certainly smell). I'm a little miffed at this right now.

From what I can see, there was a lawsuit against Audi on this sensor and they extended the warranty to 10 years or 100k miles...well I have 108k miles so I'm S.O.L on that.

I found a very reputable mechanic here in San Diego that quoted me $2k if it is the sensor, the part is almost $1400 that he has to get direct from Audi. He will check it out first and try a few other things first to be 100% sure it needs to be replaced. From what I see, there are numerous issues that could cause the sensor to go nuts.

I still get the code every day but the vehicle feels very driveable. I just hope I don't damage the tranny by driving.

I'll keep you updated after I get the engine rebuild problem fixed then take it to the mechanic for the sensor.

Dolamite

I would first ask your mechanic if he's ever worked on an AUDI cvt. Depending on how advanced the malfunctions even Audi sends the transmissions out to be rebuilt...no exaggeration. I'm curious what sensor he's talking about, reason being the multitronic trans is an enclosed system. The TCU is internal and if it needs to be recoded the tranny has to be opened and drained. The encoding is only done by Audi or by companies that have the same flashing software. The extended warranty that was done on 2006 and earlier was rebuilding the clutch pack and reflashing the TCU; this wasn't done by any ordinary euro shop. I would've spoken to the dealer and found out if they did this on your car or not. They will not tell you these things, it's your responsibility to find out. I hope everything goes okay and you get repaired, good luck. Also, let us know what sensor it is.