Hi! I recently bought a 2011 jetta automatic and have was having weird noises. Took it back to the dealership and told me it’s the torque converter but that since it’s not failing the warranty wont fix it. I wanted other opinions I’m hoping for an easier fix. 
There is a noise when letting off the accelerator as soon as you press on the gas it goes away. Everything else works fine for now but I have to sell this car in a year and a half.
The symptoms are a little unusual for it, but it may be a torque converter lock-up problem. It’s supposed to go into lock mode around 30-50 mph, and stay locked above that velocity. Lock-up is used to improve mph. When this function fails it will go into and out of lock rapidly, multiple times per second, often sounds to the driver like driving over a cattle guard. zzzzpt …
Does this descripe what you are hearing?
Hi. I tried looking up some info on this, but I don’t think that’s the issue. I was able to upload to youtube hopefully it works.
Due to technical difficulties on my end, I’m not able to listen to that file. But one idea, there’s a service bulletin for your car equipped with an automatic, about a transmission noise related to the transmission shift cable. 3712-03 dated 2.24.12. It’s described as a whistle or whine sound, noticed in the 55 to 65 mph range. You might be able to see it by googling that number.
I don’t see any bulletins related to the torque converter, at least not on the 2011 Jetta 2 L 4-banger. If you think it is a TC problem, you might want to schedule a proper transmission service, see if that has any effect.
Another idea, engines can make weird exhaust noises during deceleration. Often it is sort of a minor backfiring/puttering sound. On some older engines the cars actually had a deceleration valve in the vacuum control system to address this. On newer cars I expect it is done with a combination of the maf, vss, map, and tps sensors, and the ecm uses those inputs to figure out when to do whatever it does during deceleration to prevent the weird exhaust sound from occurring.
Another idea, the ecm is supposed to completely shut off the injectors during deceleration until a certain speed is reached, so maybe that isn’t happening. I can clearly feel it happening on my Corolla by starting at about 35 mph and steady in 3rd gear (my car is manual), then removing my foot off the accel pedal completely. The car gradually shows down to about 10 mph, when I notice it accelerate a little, which is when the injectors start firing again. You could try that, see if your car does the same thing.
Finally, do you have any engine diagnostic codes stored in computer memory? Is the check engine light on?