MK7 GTD - Real Life MPG

[Dan Burnley]

Cheers for that Nobreck, superb explanation, I now fully understand it now.
So basically if you permanently do 3 mile journeys back and from work mon-fri, you need to fly it up the motorway once in a while for a 15-20 mile journey? Only reason I ask is that my mrs drives it to and from work during the week and is a shirt distance.
A couple of years ago I had an Ibiza cupra diesel and if I put my foot down it used to kick a hell of a lot of spot out the exhaust, I'm presuming this was because it had no DPF as you explained?

[Poached]

Kind of defeats the point of buying a Diesel a bit, doesn't it?

[Sootchucker]

Yes, modern diesels are not really suited to a life of short journeys only, and do need a good run now and then to clear the DPF out.

Dealers are supposed to ask what sort of journeys and mileage you will be doing before selling you one, but a lot don't. TBH, if short journeys are all you ever do, these days, you are probably better off with a petrol - economy wise there won't t that much in it, and the petrol doesn't have the DPF to worry about.

[Poached]

Well I was also referring to having to take the car out to clear the system.

If you were in the middle of regen would you carry on until it finished?

Most people see the Combined MPG figure and think '56 mpg vs 44 mpg,that's the best for me'

[Dan Burnley]

Do you know when your in the middle of a regen, can you tell? Am I right in presuming you don't loose performance during this process?

Well in my case I wouldn't say it was an issue as at the weekends I am always doing high mileage so it will get a good run...

[monkeyhanger]

Bring in a GTI with ACT and 55mpg published combined figure and the GTD will be history for all but the 30k miles per year reps. My workmate who lives 1/2 a mile from me (we don't carshare as he gets to work for 9am and I start at 7:30 for a 3:30pm finish) has an almost identical commute to me. He just got himself an Audi A1 S-line 1.4 ACT (140PS) and with just 700 miles on the clock he is clearing 50mpg on almost every journey he does over 10 miles, including the commute to work. The interior on it is beautiful also.

[jivemonkey]

Once saturation levels exceed an upper tolerance level (think it's about 80-85% full), the ECU will turn on the DPF warning light on the dash, and the car will need to be taken to a dealership to have the active regen completed in their workshops (this is not warranty and is chargeable).

Very interesting topic indeed. My question in though, once your DPF 'Canister' reaches the 80-85% full limit and the dash light comes on, must we head to the dealer? If they're only going to do an active regen, can we not just have a good 30 minute blast on some backroads and initiate the passive regen ourselves? Would this clear it?

The GTD takes around 8 miles to get to 90C and if it decides it wants to passively regen, getting up to 94C takes another mile – leaving 3 miles each way to aim towards a passive regen.

Is it just oil temperature that indicates when the engine is able to perform a regen? Can we say that if we're seeing oil temps of 94 then a passive regen is likely to occur if required?

Fascinating stuff. 

[C2K]

Just give it a thorough Italian tune up  now and again and you won't have to worry.

[Poached]

Once saturation levels exceed an upper tolerance level (think it's about 80-85% full), the ECU will turn on the DPF warning light on the dash, and the car will need to be taken to a dealership to have the active regen completed in their workshops (this is not warranty and is chargeable).

Very interesting topic indeed. My question in though, once your DPF 'Canister' reaches the 80-85% full limit and the dash light comes on, must we head to the dealer? If they're only going to do an active regen, can we not just have a good 30 minute blast on some backroads and initiate the passive regen ourselves? Would this clear it?

The GTD takes around 8 miles to get to 90C and if it decides it wants to passively regen, getting up to 94C takes another mile – leaving 3 miles each way to aim towards a passive regen.

Is it just oil temperature that indicates when the engine is able to perform a regen? Can we say that if we're seeing oil temps of 94 then a passive regen is likely to occur if required?

Fascinating stuff. 

At that % of blocking, with the right software (Such as VCDS) you or a garage could start a manual regen.

If the filter is nearly blocked a forced regen could melt the filter from all back pressure and heat so it's probably a filter out and clean job at a competent specialist.

[corgi]

47.8 according to the bord computer on my first full tank... Mixed driving, plenty of motorway, A- road and town driving...

Impressed, so far...