Fuel efficiency: 10 mpg loss after service. What to check?

Soldato
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I had my car - a Skoda Yeti - serviced recently and the fuel efficiency has nose-dived. I took it out on a long run on Friday and instead of getting my normal 48 mpg, I got mid 30s mpg one way and it just hit 40 mpg on the return. Now, the brakes were replaced so I checked them but there doesn't seem to be any sign of rubbing. What else should I check? The car is going back for a timing belt replacement this week anyway so I'll have them check, but if I can solve it myself, I'd like to.
 
Soldato
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Is it a diesel? Was probably carrying out a dpf regen when you were monitoring the mpg. They also could have reset your long term fuel mpg reading that will take a good week or so to sort itself out to your real world average. If it's still low then ask them to check for any faults when it's in for the timing belt.
 
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Might have been "upgraded" to a new ecu firmware to .. deal with the little problem of cheating emissions the Vag group still has not been hammered for.
 
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To be honest i am properly disgusted at how lenient the Vag group has got off with this.
There is no doubt in my mind that most of the groups higher uppers knew this was going on, utter BS to suggest they didnt.
The whole lot should have been torn down and taken through the courts.

What we have had is a simple slap on the wrist, i would have crucified them whole lot of the lying scum.
 
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Might have been "upgraded" to a new ecu firmware to .. deal with the little problem of cheating emissions the Vag group still has not been hammered for.
Possibly this. If the "upgrade" wasn't performed before, they may have pushed it. The car will do more re generations, and possibly cause the failure of the EGR, as it has to work harder now and considering most of the vehicles affected will be half-way from the EGR expected life, the extra load will push for failure. Reason way VW, Skoda, Seat, etc will cover the cost of a new EGR for a while after the upgrade.
And getting ready for the aggression, I would suggest super diesel.
 
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Aye - its been mentioned before in mag letters pages but i have yet to see a proper in depth investigation.
But then the car press is in the pocket of the car manufacturers.
You just need to look at Evo's porsche fetish to see that.
 
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To be honest i am properly disgusted at home lenient the Vag group has got off with this.
There is no doubt in my mind that most of the groups higher uppers knew this was going on, utter BS to suggest they didnt.
The whole lot should have been torn down and taken through the courts.

What we have had is a simple slap on the wrist, i would have crucified them whole lot of the lying scum.
True. Considering the size and complexity of the system attached to my 2.0 diesel Mercedes, new model/engine, makes you wonder how they could achieve such miracle with a relatively simple system to coop with emissions. And must anger the people who spent hours reading Autoexpress/Autocar/TopGear and be told how bad were any other manufacturer for failing to achieve similar results from their diesel engines, or even been criticized for not offering a diesel option, plus the push from the government for people to scrap their cars and get a "band spanking new" diesel for 3k miles/year use.
The manufacturer is disgraceful, but as a company, took the opportunity created by the government, here and in other countries, and makes us wonder, again, if there was some invested interest in pushing for such a dubious solution. And the same government now, lighting a bonfire for diesel car drivers, but what other option for someone doing over 20K miles per year driving an already paid for vehicle, which already went through most of it's depreciation? How to justify selling a £10k-£12k 3 years old 60k miles car, to save 100-odd pounds a month in fuel (using electricity) but buying a £30K vehicle? In the best scenario, as I did the maths when my partner was willing to part with her A Class and get an i3 or a proper 200+ miles range electric, would take her, at least, 10 years to offset the cost of upgrade. But considering the savings in maintenance, which should be cheaper in electric cars, still, how many years to break even?
 
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I dont blame the buyer, i really dont. I can see how bad a situation folk are in for those who do silly miles - personally i would drop that right away as spending more time in a car doing nowt is not my idea of fun but most dont have that luxury.

But i am ****** that the industry has let Audi and the vag group off so easily. they should have been absolutely hammered - and the big lie that only a few knew about the cheating is just that.. lieing.
Then again when you have the ear (/balls) of the German government you can get away with anything cant you?
 
Soldato
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Was it serviced at a main dealer?

I don't believe the independents have access to the new firmware to update. Also depends on which engine your car has as to whether it is in the affected category.

What was the weather like on your journey?

The problem is there are a million factors that can influence MPG, and if you go into the garage saying that it's dropped 10 mpg since it was serviced, they'll probably fob you off that you were driving with a heavy foot. You'll probably need to do more than the one journey to show that the mpg is consistently lower.
 
Soldato
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Was it serviced at a main dealer?

Yes, it was.

and if you go into the garage saying that it's dropped 10 mpg since it was serviced, they'll probably fob you off that you were driving with a heavy foot.

They didn't - and I was on cruise control anyway most of the time. I do a very low mileage annually but come rain or shine, my Yeti, which is about as aerodynamic as a brick, has done 47+ mpg on a long run
 
Soldato
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Yes, it was.



They didn't - and I was on cruise control anyway most of the time. I do a very low mileage annually but come rain or shine, my Yeti, which is about as aerodynamic as a brick, has done 47+ mpg on a long run

What year is your car? Do you know if it's affected by the EA189 service action?
 
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