The impression I've gotten is that the V6 has fewer things to go wrong, but is more difficult to physically service due to size. Potential problems? Hard to know where to get started there... they are two entirely different engines, and common problems are also different.

 

The 1.8T has easier power upgrade potential, if that's what you want, but is prone to oil sludge or coking if cheap, non-synthetic oils are used. The turbo's wastegate may eventually burn out, and generally requires changing the whole turbo. Much of the access to things like serp belt tensioner and alternator is easier, timing belt system is simpler, and the engine is lighter with better fuel mileage than the V6.

The 90 degree 2.8 V6 is smoother, although not as balanced as a 60 degree V6, but has a big, dual-path intake manifold for a flatter torque curve. The oil has an easier life, so I go 10,000 miles on M1 0W-40. Either engine is excellent, although I prefer the six.

 

Long term (10+ years), I find them to be similar in reliability, serviceability and potential problems. They balance out between the coolant leaks, oil leaks, PCV and vacuum leaks. The V6 is much easier to drive due to it's smooth torque curve, no sudden kick of power. The 1.8T does handle a bit better due to slightly less weight up front.

 

I personally prefer the 1.8t, I've had both at one time and as far as servicing (DIY) the 1.8t in my opinion is on of the easiest to work on. I got rid of my V6 and down to my two 1.8t's and love them. They've both been reliable, although the one I bought used from a dealer cracked the head at 150K. I bought a snapped timing belt 1.8t last year, slapped a pick and pull head have had 0 issues with it. The only hassle to me on the 1.8t is that stupid coolant flange.

 

Thank you to everyone for great information. Very much appreciated.

I do really like the smoothness of the V6. That's why I bought the V6 to begin with. So, if the issues between the two engines pretty much balance out, then I'll probably wait for a V6 to come around on the local market.

The 1.8L I found on ebay seems like a pretty good deal if anyone is interested. It's got 137K miles and is selling for $2,600. It's out on Long Island, NY, which is also a little far for me to drive to anyway. btw, this was originally selling for $2,100, but apparently the guy fixed the ABS trouble code with a new ABS module. So he bumped up the price up to $2,600.

2003 Volkswagen Passat | eBay

 

What do you know that guy is in my area, the car that is

 

Oddly enough I'm looking to do the exact same thing. My wife's car is 2003 GLX with auto trans and V6 motor. She just absolutely loves the car but, man is that car thirsty. I'm thinking I've buying an exact duplicate of the car except with a 1.8t.
If I can't find one in the not to distant future, I've seriously considered an engine swap.

 

I don't have any experience with the 1.8's but with reading the forums and like others have mentioned. It's going to be a wash between the 2 with the reliability and repairs.

I love my V6. It is thirsty though. I would think the 1.8's are a bit easier to work on as far as under the hood due to the motor being smaller. Working on the interior and exterior will be the same. Insurance would be less on the 1.8's.

I have never pushed the limits on mine by stomping on the gas because I know my PCV system is on the 'Must be replaced' list and as of now doesn't leak any oil or fluids (knocking on wood) and don't want to prematurely create any. It gets out of it's own way when I need it too and I'd be curious as to what it will really do but in the meantime. I love it!!

 

Insurance would be less on the 1.8's.

Oddly enough, it's not that big of a difference. At least with my insurance. When I went looking for an B6 A4 for myself (sort of similar to the B5.5 Passat), I got quotes for both the 1.8t and 3.0 V6 and the difference was something like $6/year.

The S4 on the other hand... ?

Sent from the 7th Galaxy.

 

[2001]You'll want to go with the 1.8T, because ...

... it can "nevar lose." [/2001]

Actually, I agree with PZ on the merits of each; but ultimately, you'll need to drive a 1.8T to decide for yourself.

 

One of each (sort of) here -- 1996 Audi A4 Quattro with the old AFC 12-valve 2.8 and 2001 Passat wagon with AUG 1.8T. Same observations as everyone else -- significantly better fuel economy with the 1.8T, rock-sold reliability with the V-6 (particularly my old 12-valve -- no cam chains, etc.). My sons and I have done timing belts on two 1.8Ts (AMB twice, AUG once), on the AFC, and on a 2000 2.7T. As long as you have the official Schwaben cam lock bar (or equvalent) tool for the V6, neither timing belt is particularly difficult to do.

The 1.8T is great if you are the original owner (my case) or know that the original owner maintained it properly (my elder son's case -- 2002 Audi A4 Quattro with AMB 1.8T). Otherwise, the Sludge Monster lurks ... .