2.0 TDI 170 Fuel Consumption

[mcmahonleon]

Hi

I took delivery of an A4 Avant 2.0TDI 170 S-Line last month - I've done 5K miles in it already & so far extremely impressed with the car, apart from the fuel consumption. I drive mainly on the motorway (below 90mph) & typically only achieve an average 37mpg. This is quite disappointing vs. the diesel BMW I've just stepped out of.

I don't expect to achieve the quoted combined but was hoping to get nearer than this! Can I expect this to improve once the engine is properly run in?

Cheers in advance for your replies.

[Dave Avant]

To be honest the TDi 170 and low mpg seems to be quite common as I keep reading that either the power doesn't seem to be 170bhp or the fuel consumption is up over other models. The 170 seems to be an 'odd ball' engine where power has been extracted at the cost of mpg. I think Audi/VW need to move in a different direction with the diesel engine as I think it has peak with the technology used. After all its a a fairly old design with modifications.

BMW and Fiat seem to be leading the way with diesels, with some Japanese models following, but they don't seem as high profile.

I've got a 1.9TDI 130 and my Wife's BMW 120d. Obviously the BM is faster with 163bhp, and it revs more petrol like, but the Audi has better pick up response low in the revs, but after 3,000rpm it runs out of pull, bit like a refined old Peugeot 1.9 turbo diesel if you've ever driven one.
The BMW does give better mpg. I've runs down to London from Manchester in both and the Audi averaged early 40s whereas the BM was high 40s.

And yes it usually takes modern engine to over 10,000 miles to properly run in and give the best performance and mpg.

[a8 tech]

answer new 2.0 tdi engines comming very very soon.

[s20a4avant]

Hi, same as me ! I got mine in march after opting out of the company car scheme and drive about 65k a year but with 44k on the clock now it only ever does 40 mpg ! a bit dissapointing but other than this the car is fantastic. it also uses oil all the time which i thought might have stopped by now. mark.

[barryburbs]

Make sure you are using the expensive 'long life' oil and it should last for thousands of miles.

[barryburbs]

Keeping your tyres PSI right with weekly checks is another good tip as is not having air con on. You can also radically improve your mpg by knocking it into neutral on downhill stretches, not in the advance drivers guide, granted. I appreciate you're all talking about what the engines can 'do' but some of these suggs may help get yours up (so to speak) ;-)

[prolfe]

Keeping your tyres PSI right with weekly checks is another good tip as is not having air con on. You can also radically improve your mpg by knocking it into neutral on downhill stretches, not in the advance drivers guide, granted. I appreciate you're all talking about what the engines can 'do' but some of these suggs may help get yours up (so to speak) ;-)

knocking the car into neutral will make the car tickover - at tickover it will be around 200mpg.

Keeping it in gear and just backing off the accelerator will cut fuel altogether and the MPG is unrecordable. ie. a lot higher than 200mpg.

as it is in gear it uses no fuel and power to keep the engine ticking over - it lets the momentum of the car do that. Like bump starting it i guess.

I've averaged 41mpg in my car and the oil consumption has been better after it's first service.

Also, now that I know it can be remapped to around 210bhp i'm wondering if this could also improve the mpg.

Superchips say that they have yet to rolling road a 170 TDI that does not put out less than 180bhp as standard. So maybe that would explain the lower than quoted mpg.

[seventh-heaven]

You can also radically improve your mpg by knocking it into neutral on downhill stretches, not in the advance drivers guide, granted.

Not sure that this is true. Most modern engines petrol and diesel don't feed the engine with any fuel on overrun above a certain rev range and therefore you will use more fuel by letting it idle.

[prolfe]

Not sure that this is true. Most modern engines petrol and diesel don't feed the engine with any fuel on overrun above a certain rev range and therefore you will use more fuel by letting it idle.

Absolutely true.

200mpg at tick over
999999mpg when coasting in gear. Fuel is cut off altogether

try it when you flick the trip computer to real time mpg.

[John140]

Keeping your tyres PSI right with weekly checks is another good tip as is not having air con on. You can also radically improve your mpg by knocking it into neutral on downhill stretches, not in the advance drivers guide, granted. I appreciate you're all talking about what the engines can 'do' but some of these suggs may help get yours up (so to speak) ;-)

Surely knocking it out of gear on downhill stetches will increase fuel consumption, as the engine is using a small amount of fuel to idle, whereas on the overun these engines completely cut off fuel injection.