Jack88

If it's at an Audi dealer, you should be okay. If not, try to have it done at a proper Audi dealer. Any check at any other dealer isn't worth the paper it's printed on. It's worth noting that the performance and economy of the D4 A8 greatly exceeds that of the D3. In fact, the D4 A8 is on par or better than the V10 D3 S8, albeit with less theater.

CCKnight72

Dang now you got me second guessing this '09! I know that the D4's have 12 more hp and better gas but is it worth holding out for? A bit tricky because I don't know if I will find another one this new with this low of miles on again

Jack88

Your call, I got the impression the D4's motor may have been underrated, but the real star is the transmission. The massaging seats and ACC are both common on the D4 and so very nice, too. On the other side, a pristine D3 can still be had cheaper than your average 2011, so that's worth something as well. D3 or D4, both are very nice but it's up to you to decide whether or not it may be worth waiting a bit longer to hold out for the D4.

MP4.2+6.0

FWIW on the Seafoam: It is used by DIY'ers to deal with valve fouling issues on FSI/direct injection motors. But to my mind the Audi FSI 4.2 used in the D3 or D3 is not particularly prone to those issues to begin with. Some Audi motors are, notoriously the 3.2 V6. Occasionally you hear about it with the prior S4 4.2, but that is a somewhat different design AFAIK, and also different type of driver at least when newer. I know about the Seafoam from having done it on a Mini S 1.6 turbo motor used in the (last generation) R56--another direct injection motor pretty notorious among owners for the issue.

I wouldn't worry about it much to begin with given the few D3 or D4 owner reports for 4.2 fouling unless there is something in the car specific history relating to it. But yes, it is an option when and if needed.

cleex024

But remember there aren't many people on these forums with tons of miles on the car and even if they are pretty fouled up they will all run decently smooth. In my 335i the valves were really gunked up at 75k miles but it still ran very smooth. I know of people had valves cleaned at 15k miles and 125k miles and valves were both gunked up a lot yet it still ran perfectly fine.

So you will never know if you have gunked up valves until you open them up but most likely they will be gunked up somewhat.

MP4.2+6.0

Don't particularly agree. First, recall this is a D3 year NOT a D4 so mileage assumption is faulty. Thread is sort of convoluted though--really belongs on D3 board but a few of us w/ D3 experience from cross over point tried to help. I have been on that forum for 10 years. Average miles on a 2009 will be 8 yrs. x 12K or 8 yrs x 15K = 96K to 120K miles. FSI showed up in 2007, so these are now 10 year old, 100K cars in many cases. Net, plenty of miles for forum members there against spectrum you mention, and I have general memory of what the trends have been there on a running basis for the 10 years.

But then having owned one of those fab Mini designs as I mentioned in prior reply, aka BMW, yep they really had no idea what they were doing at least on that one in the PCV system. Fouling most commonly starts with a PCV system where the manufacturer did not think through how FSI changed the system requirements, both oil and especially cold start water vapor that mixes into a messy chemical soup. But it's very motor specific, and punchline again from now 10 year old FSIs used in D3 A8 from 2007 on is it did not come up in any meaningful number of cases on the largest English language D3 board out there; or on others like QW for that matter.

FWIW and more relevant to D4's, the fine oil separator system found in the D4 (and the D3 FSI IIRC) was a much better attempt to think this through and avoid the issue in the first place.

trippy64

As an owner of a 2012 4.2 with 125K miles, and looking to "upgrade" to a 2015, and looking to sell mine and reviewing pricing, you should be able to get a nice 2011/2012 for your price range under 100K miles.

cleex024

Whether you agree or not have you personally opened up the intake valves and taken a look in them? It's not like the guys at the n54 forums were getting robbed of performance that led them to open the valves up. They stumbled upon it by accident and decided it couldn't be good for the performance which led everyone to start cleaning the valves because they were so dirty looking...but after the cleaning you didnt gain any hp or anything from it.

A lot of people were upgrading intakes, turbos, intercooler, tubing and just taking apart a lot of engine..however no one in the d body is opening up engines and upgrading anything so no one would accidentally stumble on intake valves.

I'm not saying they are gunked up...just saying they could be but no one will know until opened up...and again even if they are gunked up doesn't mean there is anything wrong with it as I know a few people that have gone over 150k miles without ever opening or cleaning the valves.

MP4.2+6.0

No I don't have to prove everything endlessly. And this is an Audi forum, not a BMW forum. Fortunately given the many negative posts in past few years honestly, Audis are not BMW's (non) reliability wise of late. Again simply, there is a general absence of posted information over the past 10 years on the leading Audi forum in North America for the D3 (or D4 for that matter) that there is any meaningful fouling issue with the 4.2 in this configuration.

MP4.2+6.0

Yes, I have actually taken many a motor apart, including major portions of pre FSI 4.2 including a full head disassembly. W12 intake down below riser to get at thermo too. Plenty of experience with a variety of tuning over 40 years and on vs. off spec state of running generally. But I take things apart to fix known or suspected issues, not just because I read it on the web somewhere in a reference not specific to my vehicle or likely issues. Meanwhile, this is an Audi forum, not particularly a BMW forum...beyond refugees. Fortunately given the many negative typically prior owner posts floating around the boards in past few years--surprisingly so compare to say 8 or 10 years ago--Audis are not BMW's nor Mercs (non) reliability wise of late.

Again simply, there is a general absence of posted information over the past 10 years on the leading Audi forum in North America for the D3 (or D4 for that matter) that there is any meaningful fouling issue with the 4.2 FSI in this configuration. Plenty of guys are doing plenty of wrenching on D3's from the forum activity there. Core motor though continues to sort of shine as very robust and relatively trouble free. D4 is still too young for a lot of that wrenching, but in next five years this board will change quite a bit--as have the two predecessor Audis I rode though for 17 years of board evolution. There are probably as many or more FSI D3 4.2s over 4 years of (later) model run vs.two years for D4, and many more miles on those.

From being on other boards, fouling certainly can be a known issue with some FSI/DI motors, but again it is manufacturer, model and motor specific, and not generalizable as a systematic problem. FSI certainly elevates the risks for valve fouling, but there are stronger designs and then there are other now obvious sub par designs. I've cleaned and redone more than a few port heads too with fouling for that matter, generally pre-fuel injection. As mentioned, there are some references to the S4 verison as far as some fouling. In some cases it is not just the intake valves, including the Audi 3.2 where there are convoluted extra ports in the heads that foul. In D3, the only motor with really even some frequency of FSI type fouling posts is the 5.2 V10 from D3 S8 and C6 S6, which is FSI. On the order of 1-2 a year sort of stuff on D3 board for the V10, so not rampant.