jigaro

Hello.

couple years ago i posted on here saying i was about to purchase S8, i keep thinking about purchasing D3, but still cant decide, i drive x5 e70 and running cost for D3 cant be any higher then x5.

What opinions do you people have regarding 4.2 TDI 08-09 model? from what i hear its great so much torque, still has nice fuel mileage, and 0-100 time is 5.9 seconds, for me that's a really good golden medium.

please let me know your experiences when it comes to 4.2 diesel.

thank you

tx170754

Somebody from over the pond could eventually help you since we don't get the 4.2 TDI here...

Jack88

I've heard good things about it, but no personal experience.

Pothole5000

I really wish that engine was available here in the D3, I would be all over it.


Again, you will have to wait for someone not in North America.

Turbo Tony

That was actually the car I began looking for, but I have been unable to find one that's specified 'right', so I've switched to looking for an S8 instead.

jigaro

i know its only available in Europe, i guess someone in Europe would have to give more info, most cars that are for sale have 170-250k mileage (in km), but since diesel has way more to give as an engine in its lifetime i don't really see a problem with that.

from what i have heard it has tons of torque, and in general 08-09 model has a very nice ride as well.

i was always skeptical regarding diesel in general but recently i had my friends 09 ML 320 cdi for couple of days and it was tons of fun, low fuel mileage and speed was never an issue.

i hope i can hear more from our European owners

NOR_KNet

I have a 09 A8L with the 4.2 TDI engine.

It had 326hp and 650nm torque original but i have removed the particulate filter and gave it a stage 2 tuning and it should be around 400-420hp and 800-850nm torque. Sure gives a good punsh when you hit the 2200rpm and you have all torque at your disposal.

Its good on fuel milage in difference to petrol but it dosnt have the petrol v8 sound though

I took a gearbox oil and filter change before i tuned it because i dont know if the gearbox can handle so much torque. Some say it can handle ALOT more but some say 650 is the maximum. I havent tried the car against and S8 or W12 yet but some say its faster due to the increased torque and hp but im not sure.

I also replace oil and filter on the engine every 5000 km.

volvopentaman

It's a good engine, good torque and somewhat okay fuel economy.

Tough to say, comparing the fuel economy to a W12, you can't say it's amazing.

W12 can get to 9L/100km, if driven carefully. 4,2TDI can get to around 6,5L/100km.

If you have no so called "diesel tax" as we have in Finland, and you drive a lot, the 4,2TDI is a good choise.

The biggest issues with a 4,2TDI compared to a gasoline engine in the D3 is, that the intake runner flaps will have to be replaced eventually, they are a common failure on both V6 and V8TDI:s. Another service issue is of course the glow plugs, but of course the gasoline engines have their spark plugs instead.

One common issue on TDI engines is that they usually start having a fault code on "too high boost", almost every TDI engine develops it. No problem if driven carefully, but it cuts down power if you overtake. NOT FUN to have power cut down in the middle of overtaking a car! No such issue on gasoline engines in these, as all are naturally aspirated.

All bigger engines V8TDI, V10 and W12 have timing chains in the rear of the engine, so that's an even game there.

And about driving these engines. W12 and V10 have excellent engine braking characteristics from higher speeds (80km/h upwards), but city speeds the V8TDI takes the prize.

Running costs are quite the same on these, bigger gas engines have more engine oil, so they cost a tad more to change the oil.

Fuel costs are cheaper on the diesel, can't beat that. If you drive like under 20.000km a year, the gas engines are reasonable, but of course cost more than diesel.

In Finland we have a so called "diesel tax" in addition to road tax on diesel cars. A W12 has around 500€/year road tax, and a V8TDI has around 1000€/year. So you need to save up the around 500€/year on fuel and service costs to make the TDI reasonable here.

My friend has a 4,0 V8TDI 2005 model, and he drives mostly in the city, gets an average of 16L/100km in the city and 7L/100km on the highway, his average is 13L/100km.

I drive mostly highway with my W12 and get 10L/100km on the highway (heavy pedal) and 16L/100km in the city. My average is 12,3L/100km.

My friend has only got like 25.000km on the car in over 4 years, so he drives 6000km/year. I put 43000km on my last W12 in rougly 2 years and now 22000km in a year on my 2008 W12.

Our running costs have been in 4½ years we have owned the cars:
4,0 V8TDI
- 3x oil change, filter 25€/pc and oil 8,5L (Castrol 8€/L in 20L canister) *3 = 279€ for oil changes
Fuel filter 40€
Glow plugs 8x 100€ together
Polishing front lights and replacing 2 rear totally 500€
New fluids for power steering and coolant 100€
2 new tires 200€
Fuel 3250L on 25000km x 1,23€/L average = 4000€
Car taxes 4x 1000€ roughly
--------------------------------------------------------
4616,5€ excluding coolant+ps fluid + polishing lights etc = 0,1846€/km
5216,5€ incl fluids + repairs 0,20866€/km
7016,5€ including road tax but NOT diesel tax! 0,28066€/km
9216,5€ including road taxes AND DIESEL TAX,EVERYTHING! 0,36866€/km

W12:
4x oil change 12L x 4 + 4filters 25€/pc =484€
Spark plugs + air filters (bouht as a package for 250e with oil and cabin filter) = 170€
8 tyres (one set of winter and summer) 1400€
Fuel 7995L on 65000km x 1,45€/L = 11592,75€
Thermostat on both cars (got one from the dealer under warranty, paid 300€ for the second)
Car taxes 4x rougly 500€ = 2000€
---------------------------------------------
13646,75 excluding repairs, but including tyres = 0,20995/km
13946,75 including reparis, excluding road tax = 0,2145€/km
15646,75 including everything = 0,2407€/km

I did NOT put swapping front upper bushings on both cars and swapping tranny oils on all three here, as the costs were the same on all cars, I just wanted to note what the running costs are per year and kilometer.


So you can see that with little driving the V8 TDI is more expensive to own HERE IN FINLAND than a W12 that is driven more. (24cents per kilometre versus 36cents). But if you don't have diesel tax, we get down to 24 vs 28 cents, still bad for diesel. If you have no road tax at all, then the W12 is a tad more expensive (21,4cents versus 20,8cents).

But take into account that we have a W12 with 22000km per year here and a V8TDI with 6000km/year!


So to sum up:

V8TDI
+Fuel economy (avg9-12L/100km)
+Somewhat cheaper to serve (no ignition coils to break down, but glow plugs instead)
+Better engine braking characteristics in the city
+Better fuel economy for heavy towing
-Develop boost problems, possible turbo problems
-Intake runner flap problems

W12/V10
+More power and performance
+Better engine braking characteristics on highway speeds´
+No problems with intake runner flaps
-Worse fuel economy (avg 12-14L/100km)

jigaro

Nice info, good review, now you are making me think even more, S8 is not an option anymore, it needs too much fuel, if i had a choice i would get W12 over S8.

We have no diesel tax or anything like that, all i have to do import the car start it up and drive that all. Also we have many shops here who sell second hand car parts, anything we need we never go to Audi or BMW center, we just go to these shops who import crashed or old cars from European countries and sell these cars in spare parts, so i can get most parts here cheaper then dealership offers.

im thinking and thinking hard, because before the only option for me was a W12 or S8 but now 4.2 is in the equation for me.

really nice review, only think i would think about more is the fact that, W12 is a car where seating in the back you get more joy and pleasure, then driving it, S8 is a pure drivers car, you are more involved and its more fun due to V10 its sound and aggressiveness of the car, and i was thinking 4.2 TDi would be a better choice somewhere between these two, plus fuel economy.

My car must have cooled seats, back up camera, B & O, extended leather, keyless go, 4.2 TDI is loaded with such options so i guess it could work for me. but just like you said diesel problems, in my country the diesel quality is terrible, really bad, and diesel cars develope tons of problems here so this scares me a little

chokboywonda

Mine is a 06/07 and I absolutely love it. I'm at 90,000 miles now and plan to run it for as long as I can and then I'll get another one, D4 or D5.
Had normal D3 issues with MMI screen gears and compressor the only thing diesel specific was dpf filter needed regenerating.I was going to remove it but was advised not to by my MOT guy.
If I were you i'd just go and drive all three and see what you like the best.