Abnormal high fuel consumption

[tomplast]

Hi,

 

I have had this issue for over a year now that my fuel consumption have become really high and with the current fuel price it's very noticeable. I'm trying to be gentle with the throttle and minimizing my fuel consumption whenever I drive but no matter I often end up with a average fuel consumption of 7.5l/100 km. I'm almost certain that it was at most 6-6.5l/100 km a year ago.

 

It feels many times when I'm driving like the car is not "in time", sometimes when I'm letting go of the throttle and it's a slight downhill the car can still use up to 3-4l/100 km of fuel even after a few seconds. Other times the car ain't using any fuel like it's supposed to but I have failed to see any patterns here.

 

The car is a Skoda Roomster 1.6 2008 year's model, automatic gearbox and running on gasoline.

 

What have been done to try to fix it?

- The fuel injector filter have been replaced. Didn't do a thing.

- The sparks have been replaced. Didn't do a thing.

- The air filter have been replaced. Didn't do a thing

- The oil was replaced last year or the one the before that. Cannot remember if it became worse after, but at least not better.

- Have tried  fuel additives twice that was supposed to clear up any buildups in the engine. Didn't notice any difference after that either.

 

P.S I have a ODB2 connector so if you want me to sample some test data from the car then please do tell me. D.S

 

Thank you for any assistance!

 

Best regards

Tomas

[Warrior193]

Hello Tom, welcome to the forum.

While not fantastic, 7.5 litres per 100 Km equates to a little over 37.5 mpg - which, depending on type of driving style and trip, is not all that bad - I wouldn't call it 'abnormal'

You quote your previous consumption as around 6.5 litres / 100 km a year ago - this makes a little under 6 mpg difference.

Are your tyre pressures correct? This can make a significant difference to fuel consumption. 

You seen a little uncertain when the oil was last changed - it is entirely possible that the oil used was not the correct grade, this could make some difference.

How many miles since the last oil change - and how many miles do you travel per year? 

[Ootohere]

?

What oil has the engine been given at the Oil & filter change?

 

Lots of parts of which some are consumables to get a bit more MPG.

But then spark plugs do need changing periodically.

As do Air & Fuel filters.

 

Not likely to be of any matter to the consumption but i take it the tiptronic gearbox has never had an oil change.

 

The 1.6 petrol has never been that fuel efficient. 

Were the tyre changed at any point maybe giving a different indication of fuel use?   What petrol is used is it 95 ron E5 or E10?  In which country? 

 

http://parkers.co.uk/skoda/roomster/hatchback-2006/16-16v-se-5d-tiptronic/specs

 

Edited 6 August, 2022 by roottoot

[Ootohere]

PS

Have the brakes been serviced?   Not binding a bit!

http://briskoda.net/forums/topic/479681-squeaking-sound-after-a-while-driving

 

[ChrisTids]

I would start with the rear brake calipers, if the handbrake adjuster has been used to make the handbrake work effectively it would point to the rear brakes binding on. 

[Robjon]

Hi Tomas and welcome to the Forum.  I still miss my Roomster Scout, which I consider the best car I have owned in fifty years of motoring.

 

I still have the Skoda Roomster brochure from 2009, which includes spec. of the 1.6 Tiptronic.  Fuel consumption is given as:

 

Urban 27.2mpg (10.4 litres/100km)

Extra Urban 45.6mpg (6.2)

Combined 36.7mpg (7.7)

 

I agree with @roottoot and @Warrior193 that the 1.6 engine is not especially fuel efficient and that the fuel consumption figures you quote are not bad at all. Also remember the Tiptronic gearbox is not as efficient as the DSG fitted to later Roomsters.  If I've understood the operation of the Tiptronic correctly, its fluid flywheel causes efficiency losses in every gear except top. This is the main reason the Urban fuel consumption is comparatively poor. 

 

So my gut feeling is your Roomster has very few issues - if any at all!

[tomplast]

On 06/08/2022 at 08:36, Warrior193 said:

Hello Tom, welcome to the forum.

While not fantastic, 7.5 litres per 100 Km equates to a little over 37.5 mpg - which, depending on type of driving style and trip, is not all that bad - I wouldn't call it 'abnormal'

You quote your previous consumption as around 6.5 litres / 100 km a year ago - this makes a little under 6 mpg difference.

Are your tyre pressures correct? This can make a significant difference to fuel consumption. 

You seen a little uncertain when the oil was last changed - it is entirely possible that the oil used was not the correct grade, this could make some difference.

How many miles since the last oil change - and how many miles do you travel per year? 

 

Maybe it was even lower than 6.5, I'm not exactly sure - but I'm pretty sure it wasn't higher than 6.5 anyway. I have felt over the last year or so that the MPG is getting worse and worse. I love to "compete" when it comes to saving fuel and but now I'm struggling to keep it at 7.5 litres / 100 km, to achieve this I many times drive 10 km/h slower than allowed speed - or else it wouldn't been possible. With the fuel prices to day I am even more aware of how I'm driving. I'm pretty sure I can / should be able to get it down to 6 litres / 100 km.

 

Not sure about the oil change but I can tell you that the last few years I have traveled at maximum 10,000 kilometers (6213,712 miles) each year.

 

[tomplast]

On 06/08/2022 at 08:51, roottoot said:

?

What oil has the engine been given at the Oil & filter change?

 

Lots of parts of which some are consumables to get a bit more MPG.

But then spark plugs do need changing periodically.

As do Air & Fuel filters.

 

Not likely to be of any matter to the consumption but i take it the tiptronic gearbox has never had an oil change.

 

The 1.6 petrol has never been that fuel efficient. 

Were the tyre changed at any point maybe giving a different indication of fuel use?   What petrol is used is it 95 ron E5 or E10?  In which country? 

 

http://parkers.co.uk/skoda/roomster/hatchback-2006/16-16v-se-5d-tiptronic/specs

 

Not sure about the oil, I know I bought some which was recommended for the car. Spark plugs and air/fuel filters have been changed before, didn't help. I live in Sweden and as we try to be so extremely environmentally friendly here we put things in the fuel to lower the emissions and - most likely - how far we can travel.

 

Tire pressure is checked regularly and using the recommended pressure.

[tomplast]

On 06/08/2022 at 09:00, roottoot said:

PS

Have the brakes been serviced?   Not binding a bit!

http://briskoda.net/forums/topic/479681-squeaking-sound-after-a-while-driving

 

 

I have actually not had that issue for a long time now, apparently it disappeared.

[tomplast]

7 hours ago, Robjon said:

Hi Tomas and welcome to the Forum.  I still miss my Roomster Scout, which I consider the best car I have owned in fifty years of motoring.

 

I still have the Skoda Roomster brochure from 2009, which includes spec. of the 1.6 Tiptronic.  Fuel consumption is given as:

 

Urban 27.2mpg (10.4 litres/100km)

Extra Urban 45.6mpg (6.2)

Combined 36.7mpg (7.7)

 

I agree with @roottoot and @Warrior193 that the 1.6 engine is not especially fuel efficient and that the fuel consumption figures you quote are not bad at all. Also remember the Tiptronic gearbox is not as efficient as the DSG fitted to later Roomsters.  If I've understood the operation of the Tiptronic correctly, its fluid flywheel causes efficiency losses in every gear except top. This is the main reason the Urban fuel consumption is comparatively poor. 

 

So my gut feeling is your Roomster has very few issues - if any at all!

 

Maybe you're right, I could be mistaken.. But at the same time I have been annoyed the last few years about the getting worse and worse distance. Maybe nothing is wrong with my car, maybe it's just those additives the government is putting into the fuel to lower the emissions then..

[Ootohere]

The oil matters then and if it was not Long Life oil and i do not think the Service Code for your car was Long Life Servicing then the Oil needs changing annually or at or before 15,000 km. 

 

 

Brakes still benefit from servicing even if not making noises. 

 

PS

You get Winter Grade petrol some months of the year in Sweden.  But that is not a bad thing. 

 

The Government adds nothing to fuel, but have they changed what you can buy, is it E10 95 ron or is it E5 you get.

So more Bio if E10,  but then some engines love ethanol. 

 

In the UK that changed last September, and 95 ron is now E10 and Super Unleaded 97 or 99 ron is E5. 

 

This is what is sold in the UK when people by Super Unleaded , so E5.

Edited 9 August, 2022 by roottoot