What should I know about a B6 A4 1.8T AT before buying?

jsausley

Well-Known Member
Joined
Jul 25, 2010
Messages
1,222
Location
Burlington, NC, United States
Car(s)
'16 Audi S5, '14 CC R-Line, '12 Ariel Atom 3
I have the opportunity to buy a 2004 Audi A4 1.8T with automatic transmission at a really good price. It's a nice looking car, I haven't sat in or driven it yet, but the body is in great shape, the paint looks great and it makes me think the car in general has been taken care of.

The car has 140k miles. I would be buying it just to put miles on it until it blows up and I can retire it, basically. At this price, if I can get another 50,000 miles out of it without a major malfunction I'd be pretty happy. Not going to mod it, race it, drive it really anywhere that isn't to and from work or to get groceries and so on.

So what should I expect? I know that the 1.8Ts have occasional water pump failure from the plastic impellers and I know that the timing belt service should have been done around 100-110k miles. Assuming the timing belt service is done as it should have been, should I replace the water pump with the ECS metal version? How much does that usually run in labor?

I haven't had a chance to go over the car meticulously yet but I will be doing so soon, hopefully. What are some issues that I might expect? I don't even know what kind of transmission this car has, it's an automatic but is it a traditional automatic or is it CVT? CVT is probably a deal breaker, I've heard about those reliability issues and how expensive they are if they break.

How's the stock turbo on the 1.8T? Should it be in good condition is the car has mostly highway miles and hasn't been abused?

Let me just say that it's a REALLY good price, so I'm hoping that any small things I need to upgrade or change maintenance-wise won't cost too much.

Anyway, any basic suggestions on what to look for and what to expect would be appreciated. I know we have a handful of 1.8T guys around here.
 
Oh, don't you dare! I'm the only one with a B6 A4 around these here parts!

Just kidding. :p

If the turbo on the petrol engine is as tough as on the diesels, it's almost bulletproof. I would suggest lowering it slightly and putting on at least 7.5J wheels with wide enough tyres (if it doesn't have them already) to kill some understeer, although without a steel lump under the bonnet, it'll be less nose heavy than mine already.

In regards to stuff that might go wrong, I've had to replace the clutch plate, a piece of steering linkage, a brake sensor and the passenger side front window actuator arm and nicjasno helped me fix the buffer on the glove compartment lid in the past 18 months. Minor and relatively inexpensive stuff, no major faults, unlike the B5, which broke its suspension every 12 months.
 
The B6 1.8T had a nasty occasional habit of grenading. Dunno if they'd fixed it by 04 but the 01-03 was basically made of explodium.
 
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I have a 2002 A3 1.8T 150hp, I never heard of any case of 1.8T engines made out of explodium on our local forums, but there are two common problems with 1.8Ts: oil sludge and ignition coil failures. Oil sludge shouldn't be a problem if oil changes are made regularly, I do them at about 7-8000km just to be on the safe side. My car has about 224000km and the first ignition coil failed at about 221000km(all four of them had a manufacturing date of 2002). After I bought 4 new ignition coils I found out that the dealer would have had them replaced for free, but the dealer was nice enough and offered me 4 new ignition coils in exchange of the original ones anyway:D.
I have a couple of friends with B6s, but I can't rembemer any issues they had that couldn't appear on any car of that age. B6 is a nice car, I prefer the design over that of the B7(B6 and B7 are basically the same car).
 
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That's a photo of a B5. Just how reliable is that website?
 
That's a photo of a B5. Just how reliable is that website?

It's Edmunds.com, so pretty reliable. IIRC, we didn't get the B6 until 02 - I was pointing out that the 1.8T (common to both B5 and B6) had some serious problems from 01-03 here in the US. I have heard that some 04s have the same problem as the earlier cars and some do not (might be a split-year thing - as with the 2000 Jaguar V8s having some with the Nikasil engines and some with conventional iron cylinder liners). 05 on doesn't have the engine failure issue but the timing belt goes prematurely and should be replaced early.

FYI, engine oil sludging has been observed in vehicles that were not beat on and were strictly serviced by dealer techs at the factory intervals. It doesn't just appear in neglected or abused vehicles only, and VAG products in the US were known to have issues with this problem from 97-04.
 
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That's kinda a vague description. As I said, oil sludge can be a problem on this engines and that of course could cause an expensive engine failure...but that can be easily avoided with regularly oil changes. This doesn't mean that the engine is made out of explodium. In Europe the 1.8T was a very popular engine and used on a lot of VAG cars(Audi, VW, Seat, Skoda).
 
There are quite a few 1.8Ts in my town I see every day. Still going strong, even on the old B5's.
 
That's kinda a vague description. As I said, oil sludge can be a problem on this engines and that of course could cause an expensive engine failure...but that can be easily avoided with regularly oil changes. This doesn't mean that the engine is made out of explodium. In Europe the 1.8T was a very popular engine and used on a lot of VAG cars(Audi, VW, Seat, Skoda).

If you followed VW's recommended maintenance for a lot of those cars and performed the oil changes at the regular VW-prescribed intervals, they still sludged. Which is why they settled the class-action lawsuit against them:

https://vwoilsludgesettlement.com/

What are the lawsuits about?

Answer:

In the class action complaints which were filed beginning in January 2006, the Plaintiffs allege that the 1.8 liter turbo engines installed in Settlement Class Vehicles are prone to the formation of oil sludge and coking deposits even when maintained according to the recommended maintenance intervals and oil quality specifications. Plaintiffs further allege that the August 2004 Extended Oil Sludge Warranty (8 years / unlimited mileage) violated applicable consumer protection laws. The Defendants deny any defect, wrongdoing, or liability whatsoever and deny that this litigation could be certified as a class action for trial.

Of special note is that a 2004 would be exiting the 8/unlimited first attempt "please don't sue us" warranty about now at latest, so there might be a connection there.

IIRC, the explodium issue is separate from the sludging.
 
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Yes, I agree, the sludging it's a very known problem on 1.8T. But if the engine doesn't show any sign of sludging and oil changes are made every 5000-6000 miles, sludging shouldn't be an issue.
 
Yes, I agree, the sludging it's a very known problem on 1.8T. But if the engine doesn't show any sign of sludging and oil changes are made every 5000-6000 miles, sludging shouldn't be an issue.

5000 was the original spec interval from VW. It sludged anyway. Remember, driving conditions are quite different (in general, harsher) in most of the US as opposed to Europe.

The solution per the mechanics I've talked to seems to be to change at 3K if you are keeping standard oil in it or you can go 5-7.5K with most synthetics (which VW did not specify at the time).
 
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Thanks for all the notes guys.

I drove the A4 yesterday and the Tiptronic function on the transmission doesn't work at all. I'm not sure what might be causing that but it's telling me that I should probably steer myself away from it. I guess it could be something simple, but the possibility of it being something major and the transmission requiring repair or replacement not far down the line would definitely make it not worth it. Any thoughts on that?
 
How did I miss this?
Timing belt on these cars should be every 60K and costs around a $1000 to do. Control arms are made out of aluminum and fail every 70K or so. Power steering leakage is common around 70-80K as well. Coil packs are made out of explodium if you get the car change them for Hitachi E-types from ECS. Electrical problems are extremely common, for the engine stuff, valve cover gaskets leak easily so do pretty much all others :p Sludge can be a problem, need to use bigger capacity fuel filters from Audi (about twice the size of a normal one). Turbo rarely fails its relatively small but the diverter valve and the hoses can fail quite easily.

If the tranny is not working in tiptronic then I don't think it's a very good idea, it could be something very very basic/simple or it could be the TCU starting to go. Those ZF's are not particularly strong to begin with and are very expensive to deal with. There is also a possibility that someone played around with it using the VAG-COM, meaning that it could have possibly been "tuned".

- - - Updated - - -

I have no experince with auto-transmissions, I didn't even drove one :lol:...but DIY:Get your Tiptronic working again (W/ PICS) VW Passat/ Audi

That's for the CVT though.
 
Audi says more about you than an aggressive rude finger could ever do. Do not drive an Audi unless you are obnoxious, it's the Audi way.
 
OK there are always exceptions. ...

Try diving here any distance without some young thrusting sales man/executive ruining your day in what at one time was a BMW but is now an A4.
 
OK there are always exceptions. ...

Try diving here any distance without some young thrusting sales man/executive ruining your day in what at one time was a BMW but is now an A4.

Don't think we have that stereotype in the U.S., but thanks. :p

Anyway, as it turns out I'm not getting this A4. Thanks for the advice everyone. I'm just not sure I want to commit to a high mileage Audi for a daily driver, even if the price is good.
 
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