Skoda Octavia 2010 1.6 TDI - Skoda Octavia DPF v Shell new fuel saving diesel

Honest John Back Room » Technical matters
View Threaded
Sat 14 Aug 2010 16:12
Skoda Octavia 2010 1.6 TDI - Skoda Octavia DPF v Shell new fuel saving diesel - Crinkly Dave

Hi guys.

I bought a new 1.6TDI Octavia, with the new common rail engine, in March. It has settled down to a routine ~57 mpg over mixed but consistent motoring on Esso diesel.

Last month I noticed the adverts for the "new" shell diesel that suggests it can give you an extra 10% mpg for the same price, so I filled up with that. The MPG has dropped to 53 over a tankful.

Yesterday I filled up with their Ultimate diesel, and although the thing did seem to go better, the mpg figure for steady motorway cruising has dropped by 10% or more. I did not drive any differently.

As an engineer, I know I should not trust this one "dip", but it is noticeable. Has anyone any thoughts on Shell diesel. I really can't believe it would cause such a bit drop.

The other possibility, is that the engine management system has gone into enriched mode, to clean the dpf. I know this is a problem with Fiats, but not sure how this system is triggered in the VW group engines, and if there is a similar problem with overfuelling. Off now to check if oil level in sump has gone up, and to put this query on the Briskoda site. Anyone know of any link that would explain the dpf system in my motor before I take to the agent

Thank you

Reply | Report as offensive | Link
Sun 15 Aug 2010 00:36
Skoda Octavia 2010 1.6 TDI - Skoda Octavia DPF v Shell new fuel saving diesel - craig-pd130

In the 'Ask Honest John' section there are detailed descriptions of how the VAG and Vauxhall DPF implementations work. They will only usually post-inject when the dashboard warning lamp indicates a regeneration is needed, and you're driving in conditions that support regeneration.

If you're still getting 50+mpg I really wouldn't worry about it ... when a car the size and weight of the Octavia manages 50+, so many factors can influence mpg by 10% on a journey, such as wind strength, ambient temps etc.

Reply | Report as offensive | Link
Sun 15 Aug 2010 13:32
Skoda Octavia 2010 1.6 TDI - Skoda Octavia DPF v Shell new fuel saving diesel - Crinkly Dave

Ta for the link. Must do some more research, as I suspect someone must by now be doing a kit to remove these.

I know that mpg figures can vary over a journey significantly, but I was talking over a full tankful, not a journey. And based on brimming the tank and measuring the miles, not relying on the computer (which coincidentally is agreeing with a 10% drop)

Thanks again.

Reply | Report as offensive | Link

Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.

The Good Garage Guide