Taxi Driver Online

This is presumably the diesel particulate filter (DPF) they're talking about rather than the 'air filter' mentioned in the article.

But this reads to me like complete nonsense - can't believe even the most stop-start taxi driving would require the DPF to be regenerated twice a day, which is what the article is trying to say. I think.

And suspect what the drivers are saying is that they're having to drive the vehicle under load for 20 minutes or so twice a day to clear the DPF, rather than just idling (which would, I think, make things worse). But again I just can't see that, unless the vehicle is quite high mileage and the DPF is a bit clogged up with ash, which unlike soot doesn't burn off, as far as I know.

As for the £300 oil changes every couple of months...


Taxis to cut emissions in Scotland ‘have to sit with engines running to solve fault’

https://www.scotsman.com/news/transport ... -1-4948040


Image: Scott Louden/The Scotsman

New taxis bought to cut harmful emissions in Scottish cities will have to sit with their engines running for more than an hour a day to solve a fault, drivers have claimed.

They said the air filters on models purchased to comply with impending tougher emissions controls rapidly become clogged up with harmful pollutants such as particulates.

The solution is to leave the engine on for up to 40 minutes twice a day to clear the filter – or costly and time-consuming oil changes which drivers said were setting them back £300 a time.

The problem affects the more popular of the two black cabs with the latest Euro 6 engines, the Tourneo-based Ford ProCab.

Only taxis with Euro 6 engines will be permitted in Edinburgh city centre from 2022 and Glasgow city centre a year later.

Edinburgh taxi driver Danny Tebb said his ProCab has had to have four oil changes since last December.

Colleague Richard Dourley has had nine in 18 months.

Tebb said: “I’m livid. The Euro 6s are clearly unfit for taxi driving. Ford has produced a prototype software update that allows a driver to manually initiate the filter clean (as an alternative to oil changes).

“We have worked out each driver would need to do this twice per day. That’s 40 minutes twice a day sat stationary with the engine running to clean the filter.”

David Facenna, sales director of Glasgow-based Cab Direct, which produces the ProCab, admitted the Euro 6 standards had “stretched” manufacturers.

He said: “There appears to be knock-on effects for vehicle maintenance, including more frequent oil changes.”

Ford said it was “willing to hear” from drivers with “major issues”. It said: “Short stop-start drive cycles generate more particulates, which is well within the filter’s ability to handle and avoid clogging via a regeneration cycle when the engine’s up to temperature, running for 20 minutes and under load.”

What a load of tripe!

Clogged Air filter ???
£300 oil change instead of a DPF regen???
Manually initiate a DPF regen???

As far as I know, the software update only allows the drivers to switch of the ‘oil service required’ light.

40 mins to regen a dpf

whatever happened to 10 mins revving the engine in 3rd at 70mph to get it hot enough

_________________
Taxis Are Public Transport too

Join the campaign to get April fools jokes banned for 364 days a year !

I have a Ford Euro 6 engine and never had an issue like this.

Maybe it's a different engine, and maybe I do a bit more motorway work, but other than that it's all utter rubbish.

_________________
IDFIMH

I'd suggest it's not utter rubbish at all. The euro 5 and euro 6 buses I drive rarely achieve the optimum operating temperature in London as they sit in traffic idling most of the day. It's a known problem with a lot of euro 6 engines, hence the need for more frequent oil changes and very expensive visits to the local Eminox dealer. to replace a bus filter can cost several thousand £££s.

No matter what is devised, there is always the unexpected side-effect, and with euro 6 this is one of them.

My previous Mondeo was an Euro 5, and that had service intervals of 12,500 miles.

My current Euro 6 Mondeo has service intervals of 18,000 miles.

Maybe it's a different oil.

_________________
IDFIMH

Yes these manufacturers will do anything to extract money out of this trade.

So the Euro 6 DPFs are more problematic than the Euro 5s, which seemed to be less problematic than the very first DPFs which I think appeared in VAG cars around 2006?

Or is it just a particular problem with this Ford engine in this vehicle?

Anyway, I don't doubt what you say about engines in London failing to 'achieve optimum operating temperature' because they're sitting idling in traffic most of the day.

But in turn that points to one of the mysterious things about the article - it seems to be saying that to regenerate the DPF they're actually having to sit idling over one hour per day? And they seem to be talking about the 'active' regeneration process, where extra fuel is injected to burn off the soot which can't be burned off normally because the optimal temperature can't be achieved.

Which would make things worse as far as I can make out - sitting idling wouldn't help the regeneration process at all. In fact I'm sure I've read that an active regeneration will be terminated if the vehicle is idling excessively, and the engine will try again later when the vehicle is being driven normally (although that's one of the things that varies between manufacturers).

Anyway, I just can't see how idling would help regeneration, whether it's the normal 'passive' regeneration where the exhaust system reaches optimal temperature (best achieved on a motorway run in a lower than normal gear) or the active process (which I think is how the oil becomes contaminated if it's not going to plan - the extra diesel can end up in the oil if it's not ignited properly)

I'm not all that well up on modern technology as my own bus fleet is all over 50 years old, hammer and spanner technology and usually exempt from LEZ/ULEZ regulations. The modern buses I drive to TfL spec have various lights that tell the driver what it's doing, not as though it is any concern of the driver. Sometimes they go into auto-clean-the-filter mode and idle at a higher speed than normal. but from what I've read in the engineering press the lowest emissions are achieved by such vehicles being uses at motorway speeds, with lorries doing the best as they run flat out at 56mph all day on motorways (Dartford Crossing excepted .

With every bit of legislation there's always a law of unintended consequences, and with the ULEZ technology having to run engines fast is one of them.