Hi All.  A friend of mine has a Octavia 2.0 CR (140bhp) diesel DSG (FL) estate.  The car has had, what we think, is poor fuel economy since he bought the demonstrator 2 years ago.  I think it is on variable servicing and has had atleast 1 service in this time.  The Skoda garage say there is nothing wrong, indeed they have run a diagnostic check which shows nothing.  I have run a scan with my VCDS and nothing a miss.  The issue is, we would expect the fuel economy to be in the low 50's, indeed if the fuel economy were 50mpg or above he would be very happy.  I know we won't get to the manufacturers figures. 

 

What is rather odd that on long runs, not thrashing the engine, just normal 70-80mph on the motorway, I would expect over 50mpg but it does low 40's, 42-42mpg is more of an average.  Also the car does better mpg when the air temperature is warm and less whan it is cold which is the reverse of what we expect.

 

Skoda is at a loss and basically washed their hands of it, dealer saids it's fine and Skoda just agree with them.  I think the only thing that has been changed is the lambda sensor, not sure which one and if the car has 2 or not. 

 

Suppose what I am after is, does 42-43 seem resonable with other owners of this car?

 

I have VCDS, what checks can I do with this to see if something else is not reading, measuring something correctly that would give this bad fuel economy?

 

I think maybe the MAF could be an issue but not sure how to check it with VCDS?

 

Thanks all.

Mines the same highest ive had from my 170 is 44.2 even on motorway

I have a manual 140bhp 2.0tdi, only done 4000 miles so far. Getting 55-58 mpg doing 'A' road drives 50-60mph. Motorway 70-80mph returns 50-52 mpg. Towing the caravan returns 34-36mpg. Quite happy with those figures.

Just driven  95 miles in my 2012 diesel vRS DSG (mileage 12K) with approx. 45 miles on motorway/dual-carriageway and the rest on A-roads.  Maxidot reported 48.2mpg and I wasn't hanging around. 

It really can be down to the way you drive and I do mean it nastily.

Just squeezing the pedal a we bit more and changing at the wrong time can make a big difference to mpg.

On my way home driving sensibly, making a conscious effort to be super smooth and avoid excessive acceleration I regularly get 48-54 mpg but if I give it a we bit more right foot here and there it will give low 40's and even drop into the 30's very easily, my journey time is not really any quicker, just means I'm up behind the car in front a lot quicker or braking harder.

My wife can drive any car I have and she always gets better mpg than me... Grrrr.

Hope you get it sorted if it is a genuine problem.

Mpg will be worse in the winter due to longer warming time for the engine and winter diesel at the pumps anyway, but I agree you should be getting much more than that!!

My vrs 170cr easily achieves mid forties even on short commutes and high forties or low fifties on nice a road driving.

Mines the same highest ive had from my 170 is 44.2 even on motorway

Mine too

 

I have a manual 140bhp 2.0tdi, only done 4000 miles so far. Getting 55-58 mpg doing 'A' road drives 50-60mph. Motorway 70-80mph returns 50-52 mpg. Towing the caravan returns 34-36mpg. Quite happy with those figures.

Not relevant as the Thread is asking about the consumption on a CR 170 vRS, not a 140 tdi which is known to have a better mpg

On a slow run at around 60mph on motorway going to Wales I managed to get 68mpg.

Coming home I kept it at around 70mph  and got 58mpg.

This is according to maxidot which checked against Fuelly app is about 3mpg out.

My overall consumption for mainly short journeys is 50mpg.

 

The thread title is "Poor fuel consumption on 2.0 CR diesel"

Edited 9 September, 201312 yr by BEK

Mine too

 

Not relevant as the Thread is asking about the consumption on a CR 170 vRS, not a 140 tdi which is known to have a better mpg

Actually Chris , I think his friend has a 2.0 CR 140 as mentioned in the first line of the OP thread?

Unless I have lost the plot too;)

Also the car does better mpg when the air temperature is warm and less whan it is cold which is the reverse of what we expect.

 

When the air is warmer, the oxygen density is reduced (so 1 litre of air at 30degress contains less oxygen than air at 0degrees), and because there is less oxygen when warmer the ecu doesn't need to put in as much fuel to get the correct mixture. VWAG's official line is that for every 1degree increase in temperature, the fuel economy improves by 1% also.

 

Does your friend leave braking til the very last minute? It's easy to gain a few MPG by backing off the throttle and engine braking upto a junction that you know is coming up etc.

Tyres, tyre pressure, driving style, wheel/suspension alignment issue? Dodgy sensor which is giving the wrong reading but within the right range (confuses the ECU and doesn't trigger a fault).

Sent from my Nexus 4 using Tapatalk 4

Although not relevant in terms of engine but an observation with driving a DSG.

 

To get good figures you need to be very light on the throttle. Just a little tickle to get the box changing as early as possible. In some situations it can be more economical to press a little harder build the speed up then back off the throttle coast a bit then back on to maintain the speed.

 

Think of the throttle as being a tap. Every time you touch it you turn on the tap that pours fuel out. Whenever you're off the throttle the tap is off.

 

I've got some really good figures thinking like this while driving the DSG.

 

The beauty of the DSG being that under light loads and light throttle input it will change up early and allow you to coast easily and keep moving with very little throttle needed.

 

Phil

I have a friend who has a vRS Blackline 170 CR with DSG and he gets about the same, low 40's.

My manual vRS gets 50+ easy. As advanced as the DSG system is, it was never designed in mind for a diesel. It was initially the 2.0 TSI unit on the Golf Gti, but VAG obviously seen a versatility opportunity for it.

On a slow run at around 60mph on motorway going to Wales I managed to get 68mpg.

Coming home I kept it at around 70mph  and got 58mpg.

This is according to maxidot which checked against Fuelly app is about 3mpg out.

My overall consumption for mainly short journeys is 50mpg.

 

The thread title is "Poor fuel consumption on 2.0 CR diesel"

 

Mine (manual) is exactly the same as this - what RPM is the DSG doing at 70 mph?

Can't you tell I'm a chemist?!   If you get an unexpected result always check your data and calculation.  Whenever someone posts a low fuel consumption problem most folk assume a problem with the car - my immediate reaction is "How is he calculating his MPG?"

 

Is the figure of 42-43 mpg from the trip computer?  Could just be an inaccurate computer - most read 5% or so optimistic but there are some pessimistic ones about too.

 

Is the figure of 42-43 mpg calculated from brim to brim data?  Is he using the correct conversion from litres to UK gallons of 4.546 litres per UK gallon and not the conversion to US gallons of 3.785.   If he has mistakenly used the US gallon figure then 42-43 miles per US gallon equals 50.4 - 51.6 miles per UK gallon - that is about where it should be!!

 

What is the difference between the average mpg on the trip computer over a tankful and the brim-to-brim figure?

unfortunatly we don't know how economical a driver your mate is. If he's not that good then it may well be a combination of him and the dsg box which isn't as economical as a manual. Other factors also play a part too so it's anyones guess. try putting a tin hat on and suggesting he goes for a free IAM assessment to see if his driving style is playing a major part in his mpg figures....He could even do the skills for life course as that normally both makes you a safer and more economical driver, but don't tell him I said so....

Actually Chris , I think his friend has a 2.0 CR 140 as mentioned in the first line of the OP thread?

Unless I have lost the plot too;)

Youre right..I have lost the plot!...LOL

unfortunatly we don't know how economical a driver your mate is. If he's not that good then it may well be a combination of him and the dsg box which isn't as economical as a manual. Other factors also play a part too so it's anyones guess. try putting a tin hat on and suggesting he goes for a free IAM assessment to see if his driving style is playing a major part in his mpg figures....He could even do the skills for life course as that normally both makes you a safer and more economical driver, but don't tell him I said so....

Is that directed at me?

There seems to be the odd post on here about cars which do not get near the expected fuel consumption and they always look for a problem with the car.Once you have ruled out mechanical problems or ECU and then made sure the tyres are at the correct pressure, then emptied the boot of any heavy stuff, the only thing left is the person behind the wheel and the types of journey/driving you are doing. This makes a huge difference. My wife spends far longer in lower gears and uses far more fuel but she is a good driver.

My CR VRS estate has averaged 48 MPG over the last 10k miles and this has been calculated on an iphone app, recording every fill up. My car has done 31000 miles since new in May 2012 and spends most of its time on a motorway.

 

Maybe the initial post should let the car be driven by someone else over a couple of tank fulls or the driver get some lessons from the IAM just to make sure it is not the driving style.

A summary of the above?  Three main areas should be examined carefully. 

First check the sums.  Are the quantities being measured accurately?  Are the calculations being done correctly?  Is there an error?  Is the consumption commensurate with the usage?  Are the figures solely based on the trip computer?

Second, check the car.  Windows closed.  Empty the crap out the boot.  Tyre type/pressures.  Air filter.  Brakes.  4 Wheel alignment.  (assuming the engine/drive train is as OK as you said).

Left till last as a level of diplomacy may be required.  Driving style.  This has been discussed above.

I liked the suggestion about having an IAM assessment. 

My estate will easily top 70 mpg pootling about, getting caught behind tractors and the like and keeping below 60 ish. 

A blat from Frankfurt to Dunkerque, around 600kms, cruising at an indicated mid 80's usually will see low 40's on the computer, average indicated mph, low 60's,

Very interesting posts here.  We have been checking the car the old fashioned way of filling the car, driving, filling again and checking the fuel consumption and it's low 40's.  I haven't driven the car myself but we had a drive earlier in the year from Surrey down to Hampshire and back on the A3 (towards Portsmouth through the Hindhead tunnel) and it really struggles to get mid 40's.  We were keeping to speed limits and not using excessive throttle openings to gain speed or anything like that. 

 

The local Skoda dealer has recalibrated the maxi-dot so it reads fuel consumption closer to actual and to be honest, maxi-dot is pretty close now to actual.  The car just doesn't give the mpg we would expect.  I still think something is amiss somewhere with a sensor or something like that but not sure how to check and what?  In comparison I have an FL estate 1.8TSi, average it does 35-38mpg more local journeys, on the trip we did in my friends car, I'd get middle 40's without trying.  Mine is a manual if thats makes a big difference to a DSG gearbox.  On a trip to Southern France last month for holiday I was geting high 40's as an average doing 110-130kmh (or 70-80mph). 

Mine too

 

Not relevant as the Thread is asking about the consumption on a CR 170 vRS, not a 140 tdi which is known to have a better mpg

 I accept your apology for not reading whilst I did! Thank you.

Never get less than 50 mpg average over a tank on CR vrs DSG (calculated brim to brim). Interstingly, this is slightly better than my old PD manual vrs.

As stated by many, driving style is THE main factor - my usual 18 mile journey to work will see 65+ mpg but when I'm on the last minute this same journey can drop to well below 50mpg.

Is that directed at me?

No

Is this a 4X4