2006 A4 Avant S-Line Tdi 170 Performance Issues - Please Help!

[crmason]

First time poster with no mechanical knowledge so please bear with me…

I have recently purchased a 2006 A4 Avant S-Line Tdi 170 with 72k on the clock from a well known car supermarket. My previous car was a 2004 VW Golf GT Tdi 140. I have found the performance of the A4 to be bellow what I was expecting and wonder if anybody could shed some light on whether or not my expectations were realistic or if I maybe have a fault.
On my daily commute to work I am averaging 43mpg in the A4. I used to regularly get 62mpg in the Golf. Is this an acceptable level of economy for the A4? I was led to believe from the published figures that I would get well into the 50mpg region.
I find that the A4 only accelerates well in 1st to 3rd gear. 4th to 6th just isn’t happening. This is a real problem when pulling out to overtake Lorries which I need to do a lot on my commute (hence opting for a diesel over a petrol engine).
Occasionally I notice a strong almost gassy smell coming from the exhaust.
When I am idling I notice that the engine occasionally misses and hunts.
The car did have a new fuel filter and cam belt when I bought it and has a full Audi service history. There are no fault lights or indications on the instrumentation.
The car is booked in to go back to the dealer on Thursday. What should I ask them to look at? I could do with a bit of a list if any body could help? I hear that a8 tech is the font of all Audi knowledge.

Many Thanks

[Crasher]

No that does not sound right, possibly a blocked diesel particulate filter but that should bring on the warning light. The first thing the Audi dealer will do is to carry out a fault code read and see if anything is stored and if the cam belt was not done by a main dealer, they may want to check the cam timing.

[crmason]

Thanks for the speedy response. The car is going back to the car supermarket under there warranty and not the Audi garage which is why I could do with a bit of list so they don’t just fob me off. I want them to carry out actual visual checks as well as connecting the vagcom thingy as am I right in guessing that clogged pipes and things like that won’t register on there?
Thanks for the help for heroes support

[Crasher]

If the selling company can do a proper fault code read that is OK but you may end up taking it to Audi or a specialist for a second opinion.

[gaz1965]

i also have just purchased an A4 2.0 tdi 170bhp s line and like you i am very dissapointed with the economy and performance.
i have just traded in from a Saab 9-3 tid 120 bhp and i have no doubt in my mind the Saab was quicker and much more economical i am beginning to think i have made a mistake in the purchase of my 170 bhp A4.

[stevesnaz]

As for the fuel economy, around 40mpg for a PD 170 sounds about right. Apparently there is a significant drop in economy compared with the 2.0 TDi 140, which will average 48 - 50mpg. Check out these threads for other 170 owners' fuel econ stats:

https://www.vwaudiforum.co.uk/forum/s...0+fuel+economy

https://www.vwaudiforum.co.uk/forum/s...0+fuel+economy

[Andrew170]

Does it reach normal temp within a reasonable time? I had a faulty thermostat which meant it ran too cold and really dammaged performance and economy! Also if the exhaust doesn't get hot enough the gasses condense and you'll ge todd smells and visible smoke out the back...

[robob123]

I'm two weeks into ownership of my A4 avant, s line 170. It's 35k miles, 2007 and replaced a 2004 golf 140 tdi. So I think I'm a similar case to original thread author.

My initial experience was very similar. The car didn't seem as nippy or responsive as the golf, and mpg is dispointing.

However I've decided the problem is the comparison and not the car. The A4 is clearly higher geared than the golf as at 90mph the golf would be doing 3k rpm in 6th, whereas the audi is running at less than 2.5k rpm in 6th.

The A4 is basically a more comfortable cruising car, and driven as such, rather than like a nippy hatchback I've found the mpg is improving. Also noticed much better performance on a tank of premium shell diesel. Its early days, but now I'm getting use to the car, I becoming happier with the way it drives.

Next question for me is to remap or not??? its another £300 after all!!