Hey guys. About to order my 2nd kodiaq. This one will be a sport line 4x4 automatic. The query I have is I am stuck on engine choice. I’m either thinking the 2.0tdi 150bhp which I currently have or the 2.0tsi 190 bhp as they are similar money but the mpg is 10mpg less in the petrol. We do about 9-10k miles in a year. What would you choose?

With that low annual mileage petrol every day of the week.

Any potential fuel savings from a diesel will be negated by maintenance costs of the DPF.

+1 for what Kenny said.   It may (?) also be difficult to sell on a diesel when the time comes to trade it in.

 

1 hour ago, Kenny R said:

Any potential fuel savings from a diesel will be negated by maintenance costs of the DPF.

What DPF maintenance? 

15 minutes ago, ZacDaMan72 said:

What DPF maintenance? 

Just going by the stories on here of DPFs being blocked and having to be cleaned/ replaced due to short, low mileage journeys and not ever getting hot enough to carry out regens. 

I wouldn’t know as I’ve never had a car/ tractor that’s ran on the fuel of the devil  

Edited 5 November, 20205 yr by Kenny R

My first Kodiaq survived 3 years and 30,000 miles and not a penny had to be spent on “DPF Maintenance”.

 

Haven’t maintained a DPF on any previous cars either.

 

I’m expecting current car to survive similarly.

 

Fair enough, I don’t do a 3 mile daily commute.

 

The question on fuel saving is down to simple arithmetic for the OP to answer.

 

And “trade in value” is a non-issue on lease cars w.r.t. Petrol vs. Diesel.

 

Final value is a done-deal (PCP) or non-existent (PCH).

Edited 5 November, 20205 yr by BoxerBoy

Are you buying on PCP and will give it back in 3 years?

 

If so then forget the DPF and the residual value issue and buy what you want.

 

If you plan to keep long term then maybe the Petrol ...

 

 

5 hours ago, Kenny R said:

Any potential fuel savings from a diesel will be negated by maintenance costs of the DPF.

 

To be clear, DPF has it`s own fuel injector and regeneration process does not depend on engine`s temperature.

 

But doing this low mileage - petrol all the way. Quieter. Warmer at start, if you don`t have additional ceramic heater on board.

If renting a TDI with SCR (Adblue used)  then go with one if you like how they drive.

 

If buying a keeper that you might have 4 or 5 years then be sure to purchase the extended warranty at time of ordering, especially if in the UK and not doing longer journeys or higher annual milage.

Yes there is the SCR system, but regens soon lower the fuel efficiency / average MPG.

Edited 5 November, 20205 yr by e-Roottoot

1 hour ago, linni said:

 

To be clear, DPF has it`s own fuel injector and regeneration process does not depend on engine`s temperature.

 

But doing this low mileage - petrol all the way. Quieter. Warmer at start, if you don`t have additional ceramic heater on board.

Perhaps I’ve misunderstood the purpose, here.  I thought that the heat of the exhaust, once the engine is fully warmed up, is supposed to keep the DPF operational.  If it isn’t kept clean enough through that, the injector will cause a regeneration.  BUT ... the injection and regeneration don’t continue if you turn the engine off - just the fan continues, to help dispel the extra heat that has already been produced.  If, like many, you drive only short journeys, you will cause the regeneration to start at some point, but not to complete.

 

Or have I got that wrong?

There is active regeneration and passive regeneration.

Passive is, when you usually drive long distance and exhaust gets the tempeature from the process itself.

Active is, when the soot level in DPF reaches critical mass and exhaust temeperature is not high enough, independent burning process starts.

 

If regeneration is interrupted, it will continue on your next trip. And then next, until DPF is cleaned.

 

I have 8 km to my work. Sometimes it takes 3 days and trips to work and back until regeneration is done.

I have ELM327 OBD dongle and VAG DPF app installed and from time to time I just follow the thing.

2 hours ago, linni said:

 

To be clear, DPF has it`s own fuel injector

 

 

Do you really believe that?

4 minutes ago, J.R. said:

 

Do you really believe that?

 

During active regeneration, raw fuel is injected into the diesel oxidation catalyst (DOC) to achieve appropriate regeneration temperatures in the DPF.

 

Internet.

 

Thats not what I questioned.

 

Do you really belive that the DPF has its own fuel injector?

17 minutes ago, J.R. said:

Thats not what I questioned.

 

Do you really belive that the DPF has its own fuel injector?

 

To be clear, DPF has it`s own fuel injection.

 

Not injector literally, but vapouriser.

 

Satisfied?

Edited 5 November, 20205 yr by linni

@linni

The difference with your engine is that it is built to suit being used in light commercials and used in the likes of courier vans doing lots of short drop trips.

The non Bi-turbo TSI's these days are really not suitable for taxi type driving. 

Satisfied?

 

Not really, when you use a term such as "lets be clear" its stating something to be a fact in a very authorative manner and others will take it is so, which is why I asked the question.

 

So not an injector but injection & the DPF has its own "vaporiser", are you stating that as a fact?

 

I am happy to be corrected and learn, for I am learning every day, but my the VAG self study guide on DPF systems concurs with the following published information by David Bodily VW Technical Support Specialist - "Specific measures are taken by the engine ECU to raise the exhaust temperature to above 600°c, these include switching off the exhaust gas recirculation and increasing the fuel injection period to include a small injection after the main injection" Commonly known as "post combustion" injection and carried out by the cylinder injectors and not a dedicated DPF injector or vaporiser.

Edited 5 November, 20205 yr by J.R.

Tbh thinking the petrol would be nice as at least it has a bit of power with it. Due to covid my wife (it’s her primary car as I have a company car but we use the kodiaq all weekend) working from home the mileage is likely to be lower so could be harmful to the dpf not getting the same type of running. Next time it could be electric so might as well enjoy it while I can lol

@aerodynamic18

If the next car is an EV you might wonder why you spent the last few years with less performance and a petrol car.

Not convinced here in Northern Ireland has the infrastructure for electric yet. I’m not ready either lol

That is the issue, and the VW Group EV's like the ID.4 or Enyaq might take a year or 3 until the snagging faults are sorted.

The ID.3's have been released too soon before the faults were dealt with and the owners / drivers are doing the R&D as has been the case for decades with the VW Group.

Car ordered. Thanks guys. Went petrol

2 hours ago, aerodynamic18 said:

Car ordered. Thanks guys. Went petrol

 

There you go then.  I can't imagine the above "discussion" helped very much.

 

Do you regret asking?

Nah. I was half thinking the petrol anyway. Got to love a discussion lol

On 05/11/2020 at 19:59, J.R. said:

Satisfied?

 

Not really, when you use a term such as "lets be clear" its stating something to be a fact in a very authorative manner and others will take it is so, which is why I asked the question.

 

So not an injector but injection & the DPF has its own "vaporiser", are you stating that as a fact?

 

I am happy to be corrected and learn, for I am learning every day, but my the VAG self study guide on DPF systems concurs with the following published information by David Bodily VW Technical Support Specialist - "Specific measures are taken by the engine ECU to raise the exhaust temperature to above 600°c, these include switching off the exhaust gas recirculation and increasing the fuel injection period to include a small injection after the main injection" Commonly known as "post combustion" injection and carried out by the cylinder injectors and not a dedicated DPF injector or vaporiser.

 

Some DPF equipped VAG vehicles have a catalyst located immediately prior to the DPF to help with heat generation, mostly on vehicles where the DPF has been retrofitted part way through the cars life-cycle and thus wasn't originally developed with a DPF in mind, or where restrictions meant the DPF had to be located further away from the engine than would be ideal for optimum heat generation.

 

The increased fuel injection period is used in conjunction with the catalyst.