post-emissions fix a3


New member
Jul 27, 2019
Denton, texas
2012 audi a3
Ill just run this thread, and see if anyone else is interested. these are my experiences and I am NOT an experienced tdi guy, nor am I a mechanic. Im just a guy that likes cars and likes to do his own work when possible.

I purchased a used 2012 a3 with 68k mi. It is post-emissions fix and warranty is good until December 2023 or 116k mi (I mean hot damn- not bad for a used car) I bought the car from a wholesaler who purchases at auction, I have been watching for a few months and this seemed the cheapest way to go, paid $7800 for the car. no owners manual, no maps disc, no floor mats, no spare tire, pilfered before buyback im sure, but hey the price seemed right.

Given that the car has been sitting for a few years I figured I would give her a fluid refresher, so changed oil/filter and transmission fluid/filter.

anything else anyone suggests? air filter looks good- previous owner put k&n so ill leave it be. fuel filter?
per carfax- fuel filter/pump/and tank replaced at 25k mi.
- spark plugs replaced at 55k

after oil/dsg service the car threw some check engine codes (within 50 miles)

P2002 - particulate trap efficiency below threshold bank 1
P0401 - exhaust gas recirc flow insufficient detected
8194 - no DTC definition found (something dpf related)
1025 - air bag malfunction indicator lamp ("stored mil")- not an issue?
2214 - no DTC definition found (no idea- but "stored")
1325 - no DTC definition found ("stored")

looked around on tdiforums- evidently the P2002 and P0401 are a known recurrent issue with these cars- not sure about the others any insights?
I contacted the local dealership and he said any causes of those 2 codes should be covered under that sweet warranty so Ill be scheduling with them asap. Is there anything in particular to ask the dealership for or about? my concern is that theyll hit the reset and tell me im good to go?

I am learning about this regen process, any chance these codes clear after a few regens? ive only put about 300 miles on it since i bought it...

Thanks in advance for your time!


Veteran Member
Mar 3, 2014
2011 JSW 2008 E350 6.0
Remove that P.O.S. K&N! They do nothing but clogg up your MAF and sooner than not your DPF.

Read this JSW thread


Veteran Member
Nov 6, 2009
Houston, TX
Currently none. Formerly: 2010 VW Jetta TDI 6M, 1993 Dodge Ram W250 Cummins 5M 4WD, 1990 VW Jetta Diesel 5M, 1986 VW Jetta Diesel 5M, 1980 VW Uabbit Diesel 4M. Currently driving 2018 Toyota 4Runner SR5 4WD.
Fuel tank and pump replaced at 25k? The only reason I can think of that would necessitate the replacement of those parts is that the HPFP disintegrated and contaminated the fuel system with metallic debris, in which case many more parts than just the two should have been replaced. More specifically, the fuel injectors and all the fuel lines. Prior to the dieselgate, VW/Audi usually footed the bill for that ultra-expensive repair (~ $7,000) without much questioning, and it involved literally complete removal and replacement of everything the fuel comes into contact with. Any Audi dealer should be able to tell you exactly why the pump and tank were replaced and why the rest of the parts weren't. Also, ask the dealer to run a quick load test on your battery. That should give you some idea about its condition and whether it needs replacement, especially if this is the original battery. Also, if the car had the fix done and you only put 300 miles on it, there really shouldn't be any codes. That, plus the fact that you bought the vehicle directly from a wholesaler makes me question whether the fix was done at all. Again, any Audi dealer should be able to tell you when the fix was done, what exactly was replaced/fixed and who did the work. Get all that info in writing from Audi, they must have a complete service record for this vehicle.