Strong ammonia smell in exhaust?

I have a 2015 GSW TDI 6M that had the phase 1 emissions update completed about 4000 miles ago (total miles ~31,000). Tonight while stopped at a stop sign and windows down, I noticed a very strong ammonia smell that made my eyes water and irritated my nose and throat. As soon as I started moving the smell went away. A few blocks later at the next stop sign, I noticed it again. I assume I am smelling AdBlue in the exhaust and am alarmed with the strength of the odor. Since the engine was idling at 1000rpm with the AC off, I believe I was also going through a regen cycle at the time.

I frequently drive with the windows down and have never noticed this before today. Has anyone noticed the ammonia smell in their exhaust? I checked the AdBlue injector on the DOC and there is no evidence of a leak there (no crystals). My initial thought is that something is wrong with the injector causing it to dose too much while the engine is at idle. I cannot find anyone else complaining of an issue like this through google searches or this forum, so am not too optimistic that the Dealer is going to have an answer on this one.

AdBlue (def) is synthetic urea, so the ammonia smell makes sense. I've not had a regen since I had the update done and I don't normally roll my windows down, so I've not noticed any difference. I would not be surprised if the increased dosage rate is responsible for what you are noticing.

My 2013 Passat would do this once in a blue. was rare tho

Have em take a look. The dosing device could be misbehaving, feeding too much fluid. It is definitely emission-related HW , so you dont have to worry about a thing.

In my Passat, they had to replace the doodad as it was leaking fluid.

It happens...
Have smelled it once or twice on heavy trucks doing regens if idling...
SMELLED it once on my 2015 when I drove it I to the garage and shut the car off, not realizing it was regening..
I wouldn't worry if a quick look around shows no obvious drips or white crusty junk on any fittings.
Remember....it's all under warranty.

Part of SCR. I have noticed on some SCR-equipped diesels myself. Not sure how often or how much is "normal", though.

Free ammonia should not be escaping from the SCR. If it is, they're overdosing DEF and it can't all be processed in the SCR.

I would say that a light ammonia smell is probably fine, but very strong ammonia is definitely not good.

That's the thing, it is subjective. The things different people smell can be quite varied. I get into some cars here and have to jump back out and choke back vomit they smell so awful inside. I keep a mask for these cars, but since there is no sign atop the car that says "Health hazard inside, wear safety equipment" I have to go back inside and get my gear. Yet clearly the person that drives the car has no problem with the smell.

Until there is some scientific way to quantify the smell of the SCR's exhaust (or if enough people complain about it) it will be difficult to say with any certainty what is "normal" and want is not, and what falls into the "acceptable" category, even if it is not necessarily pleasant.

I smell some diesel smell from all my non-DPF/non-SCR diesels at some point and time if I have the windows down and am stopped. I would place that in the normal category, and not something I have ever been concerned with, but I understand if some would be. Better than the awful smells from my old pre-catalyst gasser stuff.

Planning on the fix, at this point in time.

However, having a delicate nose (nausea issues) not too sure what I might do if it becomes a problem.

Add to that I very seldom drive with the windows down. Maybe nothing to worry about ~~ Hoping

The few times I have the window down (stop lights) I have smelled yucky air (diesel)

Ammonia escaping the scr catalyst is known as "ammonia slip". The amount of ammonia slip is related to the catalyst temp and ratio of ammonia to NOx. As catalyst temps decrease, the amount of ammonia slip increases. Rapid heating of a catalyst (ie during a regen) also dramatically increases ammonia slip. Some vehicles have another catalyst downstream of the scr catalyst to take care of any surplus ammonia. I'd keep an eye on the amount of DEF usage though- could be a dosing issue.

During a 10k service I had the dealer top off the adblue and it smelled like cat piss. He said "this stuff stinks so bad" but considered it normal. The DEF I used from Walmart is almost odorless so it must have something to do with the dealer stuff. My brother's 2015 Sportwagen just had to have the def system repaired because of a leak and he had the terrible ammonia smell throughout the car for days prior to that. They tried to charge him for the repair and he fought them over it because he was still within 36k warranty. So beware that they are not covering the Adblue system as long as the emissions warranty. This worries me since there is talk of class action suits being formed when peoples adblue system is failing at 50k- just outside 36k warranty

Anything emissions should be covered by the long emissions warranty stipulated in the settlement. But nobody said it would be easy. At times you will probably have to stand your ground and insist and may need some legal help as well. Lets hope things go smoothly. Sometimes it also depends a lot on the customer and their attitude as well.

Hello all...I took my 2015 Golf TDI to the dealer yesterday and was told that the urea smell could not be fixed because there was NO check engine light on even though the smell can get to the point of being nausating esp when idling ....Any suggestions esp since all of these emission systems are suppose to be warranted under their so called good job of taking care of the buyer...

Vehicle above has 77000 miles on it and runs like a scared rabbitt

Check at the DEF injector and line under the hood for white crusties. There is a TSB about it.

I actually experienced this ammonia smell for some time after the dealer changed the DEF injector...but it stopped shortly after. I was going to post or search about it, but because it stopped I lost interest ha!

Some people seem really sensitive to that smell, some don't seem to notice at all. I'll see it spilled all over the trunks of some cars, and about gag when I open the lid, and the owners never say a word... and others that are squeaky clean everywhere, and an owner that will mention it.