Dismal DPF!

[BluChris]

If the trip is like my Skoda Octavia (expect it is), you have an instant, a short term and a long term fuel use display. Instant changes constantly. Short term is for the current trip only and resets after about 2 hours idle from memory. Long term average is just that, unless you reset it of course.

Your previous figures sounded terrible to me, given my Octy is much bigger and has the old school 1.9 TDI. Long term average is 6.6 comprising vast majority of commuting K's. Suburban trips tend to range from 7.5 down to 5.8 depending on traffic, +1 - 1.5 with AC on. So I would have thought your most recent posted figs are more like it.

On the other hand if you do lots of short trips/heavy traffic it will be bad, like any car. Worst case stuck fast in impossible traffic I have seen north of 30 l/100 on the short term readout. I somehow find that perversely hilarious...

[Gigitt]

something is definately wrong.
My Mk5 Jetta CR2.0 125TDI is returning 4.5l/100km Highway and about 6-6.5l/100km in the city (13,700km on odo)

[THE_EGG]

My economy is around those figures also, and lets face it, they are not great. The reason i haven't been too concerned with the economy as yet, is im getting more bang for my buck then i was with my previous vehicle (dodgy Nissan). So im saving money, but maybe not as much as i should be?

Did you manage to get your DPF sensor looked at? When you were advised?

Nah I had too many gearbox faults to bother looking at the sensor. I was going to get it looked at once the DSG was repaired but it never was. The mechanic suggested it.

That can't be right! Your TDi's are using over DOUBLE what the older 1.9 PD TDi 9N3 Polo uses.
Something is seriously faulty with those CR 1.6 TDi engines (in your cases, at least).

LOL, my WHOLE CAR was faulty . Broken DSG too haha.

[Transporter]

I am about 10 minutes away from going for a drive. I think this calls for some research!

Will update you all with some figures when i get back

---------- Post added at 01:56 PM ---------- Previous post was at 12:52 PM ----------

Alright, test results are in.

So from the get go economy was averaging around 10L/100km around town. Then after fiddling around with the Combi Instrument's OK/RESET button (thus resetting the counter), the figures dropped to around 6.5L/100km. Which are figures i expect from the 66TDI. Im guessing highway driving would be about 3/4's worth of that?

Are the figures i was presented with at the start an accumulation of averages from the day i bought the car? So all that was required was to reset the counter to get a true reading of my fuel consumption? Or is my Polo suffering from Polio

The best way to check the fuel consumption is from the fuel docket.

[kaanage]

The best way to check the fuel consumption is from the fuel docket.

Yes, but you can also use this to calibrate your MFD by resetting the long term trip computer each time you refill fully and compare the long term MFD consumption reading against actual consumption. Then you can at least have some confidence in the short term readings (and even more in the long term readings).

So from the get go economy was averaging around 10L/100km around town. Then after fiddling around with the Combi Instrument's OK/RESET button (thus resetting the counter), the figures dropped to around 6.5L/100km. Which are figures i expect from the 66TDI. (

Grizzy, if you've never reset your long term trip readings and that was what you were reading, then that's still terrible no matter how inaccurate your MFD is (they tend to be about 10% optimistic). If that was your short term reading and you'd driven within the last 2 hours, it's still not a great figure unless you were stuck in bad traffic earlier.

[Greg Roles]

Yep this particular model seems to cop the worst DPF problems. Things to help are to use good fuel from the top three brands, avoid short runs, use Morleys smoke killer, and install a Provent if you can squeeze it in somewhere! If any of you guys are in Brisbane, I want to have a good look at one of these once Carformance is set up properly around July. Like to work on fitting a catch can, and do some testing on the DPF setup. They sure seem to suffer more that they should.

My gut feel is the DPF is either too small, or too far removed and not getting hot enough passively.

Oh and those differential pressure valves are dodgy at best.....They do need to be calibrated once fitted in Vag Com chaps under advanced coding.

[Grizzy]

The best way to check the fuel consumption is from the fuel docket.

Valid point sir!

[bluey]

That can't be right! Your TDi's are using over DOUBLE what the older 1.9 PD TDi 9N3 Polo uses.
Something is seriously faulty with those CR 1.6 TDi engines (in your cases, at least).

Our 1.9 PD TDI Polo has average fuel consumption (mostly short trip school run) after 39,500km of 7.1L/100km zig-zagging from about 6 to 8.5 with general trend downwards. The computer always seems to report better than this - it lies.

[Grizzy]

The old DPF light came on again over the weekend. I seem to be getting used to seeing it. So i took the car for a nice long trip to give the DPF a clean out as usual. The light disappeared after 10mins of driving at 80+ kms, so i proceeded to travel home. This got me thinking about my driving habits over the past few weeks. My driving over the last few weeks is as follows:

• 2 weeks ago = DPF light comes on. Take the car for a long trip to burn the ash off.

• 3 days later = DPF light comes on again. So i take the POLO for another long trip. DPF light disappears.

• 5 days of 15-20 minute trips to work. Inner city driving.

• 2 days of highway driving. Few hours long, per trip.

• 5 days of 15-20 minute trips to work. Inner city driving again.

• Weekend just gone = DPF light has come back on!

Surely i have done enough driving (80+ kph) to justify the DPF regen over the course of a few weeks?

With only 7,499kms on the clock, this is getting ridiculous! I plan on going to the Dealership this afternoon and start asking some GOD DAMN QUESTIONS!

[kaanage]

When doing the 80km/h+ runs, are you also driving at 3000rpm+ to help the soot burn out (the ash stays as the residue )

[Grizzy]

When doing the 80km/h+ runs, are you also driving at 3000rpm+ to help the soot burn out (the ash stays as the residue )

The manual suggests driving in 4th gear above 80km/h. As far as i can remember i was sitting around 2500rpm+?

[kaanage]

Our dealer told us that if the DPF was clogged and we brought it in, they'd basically drive it at about 4000rpm on the freeway for about 1/2 an hour

[Grizzy]

Our dealer told us that if the DPF was clogged and we brought it in, they'd basically drive it at about 4000rpm on the freeway for about 1/2 an hour

I have considered dropping back to 3rd gear on the highway, to get the RPM right up. But don't think i could handle hearing my new diesel moan for an hour

[AlexRO]

good old italian tunes keep diesels alive sometimes .. I have replaced the rear end of my exhaust .. and the note is noticeably different after i have "cleaned out" the dpf lol