Fickle MPG

[T6Paul]

I thought I'd start a post about how much the MPG seems to vary...

I've had my van, a 150 dsg kombi highline, for 2 months now and have covered 3250 miles in it. My trip to work is roughly a 75 mile round trip and consists motorway (75%), single/dual carriageway (20%) and town (5%) by distance. I leave early and get home late so generally I don't get stuck in much traffic...

According to the MFD the average trip can be anywhere between 28-37 MPG, but is usually between 30-32 MPG.

The van regens regular as clockwork (which I guess is a good thing?) as soon as it's filled up and again on the last block before the 1/2 tank mark.

The van is never loaded at more than 100kg, I use the cruise control on the motorway so the speed is constant.

I'm not looking to start a debate about real MPG vs claimed MPG (plently have covered that elsewhere)

I would like to gain thoughts and feedback about how it can vary so much when driving the same route?...

Thanks Paul

 

[Jonny]

Do you use cruise control as much as you can?

When you're off the motorway then that's when you foot will be on and off the accelerator constantly. That part of your journey will vary every day.

Also,

I think because the fuel tanks are so much smaller than most vans, you notice a more than subtle difference in fuel consumption on the same journey.

Starting temperatures will play a big part though. Each morning, the weather has been all over the place and we've had some pretty cold mornings still. No matter how good your deisel engine is, it's going to need a fair distance to run before it even thinks about burning efficienctly and get to an optimum running temp.

The colder it is, the longer the engine needs to burn efficienctly.

Combine a colder start with a smaller tank and not often enough using cruise control, your fuel consumption will probably vary a noticeable amount on the same journey.

 

[chriscroft]

My 204dsg 4-motion Vel(so quite heavy even when empty) hasn't made 30mpg when I measure it properly (full tank - full tank), It does about 28.5mpg.
Our journeys are usually longer ones with motorways, and we drive as fast as dare 80mph (sometimes slightly over)shhhh
But we have always run all weather tyres which are slightly oversized, and I am starting to wonder how fuel they are using over and above regular good quality summer tyres.
I have just powder coated my wheels, and have put back the summer tyres which were in the shed, so it will be interesting to see what happens???
Oh and we have ACC-cruise which we try to use, but not always. That can make a big difference on the display mpg if we stick it at 70mph (which isn't that often)

 

[T6Paul]

Cruise control on the motorway is usually on, I'm pretty good at keeping the speed constant without too...

I agree re the cold weather, but this has not correlated with the variance in MPG IMO.

 

[T6Paul]

Fill up to fill up is generally about 32mpg calculated.

 

[RattyMcClelland]

The 150ps is a turd for fuel economy. I complained to vw. Got nowhere. They even checked the van. Its very poor.
19s, 20s never made a difference, loaded, unloaded, never made a difference, cruise or no cruise never made a different.
12k mikes on mine now and I average 29mpg real world calculations on fuelly.
Best mpg was 31.5mpg on a trip to Scotland. Worse was 26mpg.

Because fuel economy is crap adblue suffers. 2750 to a tank of urine.

 

[T6Paul]

Perhaps I should consider myself lucky, so far 3250 miles and the MFD still shows 2500 miles of adblue remaining...

 

[former member]

AdBlue consumption is definitely higher than expected and WAY higher than the computer "predicts" but since using pumped AdbBlue (68p a litre) I really don't care and we're well happy with our mpg. But we do low miles and only really use it for fun. 30ish mpg for a 2.6 tonne beast with 4WD, four bikes hanging off the back AND surfboards on the roof is brilliant IMO.

Going over 70 savages the mpg - over 80 and it really suffers. Hills make a big difference too.

 

[Loz]

my last brim to brim calculation was 24mpg

 

[former member]

my last brim to brim calculation was 24mpg

Ouch!

 

[Davenjo]

150DSG Highline PV converted to camper: My last few brim to brim calculations have returned between 32 and 34 MPG. However, this is only part of the equation as our main use is camping and every refill so far will have included a significant amount of Eberspacher heater running. The MFD usually shows around 38 to 42 MPG average which I think is more realistic.

I've currently done around 2900 miles and the MFD is indicating another 3000 miles before AdBlue is required.

Most of those miles would have been done with close to the 3000kg weight limit of the van and, even when "empty" with just me driving, I would think the van is around 2500kg (most of our camping gear lives in the van with food cupboards stocked ready to go).

I have been aware of regens taking place 3 times now but only because they have not competed when I park up - first time this happened I thought the van was about to blow up. Assuming it is happening a lot more often but probably when I'm sat on a motorway in cruise so less likely to notice?

I tend to stick to speed limits, use cruise on motorways and have not yet needed to use the air-con (which I expect would account for a couple of lost mpg?).

All in (currently!) happy with the van's MPG and not seeing the sort of variances discussed by @T6Paul above but I don't do the sort of routine journeys you do to get daily comparisons.

 

[mopardave]

Ok gents.......this is a subject close to my heart! I've discussed it many times on here but if we're gonna have a dedicated thread, great.
Facts: 150 manual kombi.......5000 miles. Apart from being lined out, it's standard and running on 17" Devonports. All recalls carried out so I'm up to date. I run it exclusively on Shell V power and a diesel additive called diesel rhino.

My MFD is now affectionately known as the Multi Fantasy Display because it's laughably inaccurate (though this can be altered though apparently)......generally over reads by 5 to 7 mpg! My motoring is sympathetic to mpg....ie, not much traffic and no short trips. Worst tankful was 35.04 mpg (manually calculated) in January. Best....steady run up to and around Northumberland last week.....44.26 mpg. Regeneration occurs frequently.....can be twice a day! Adblue was topped up at 4500 miles but I reckon it would have gone to 6000 miles.
To get those figures, I drive really steady.......loads of anticipation.........rarely use cruise.........no short trips, blah, blah, blah!
Ratty would say they're good figures......and compared to his, they are......but considering the type of motoring I do, I think they're ok......no more, no less. What disturbs me is the lack of consistency and the amount of time my fan (jet engine!) operates.
Personally, I'd have preferred petrol......but that's a whole new thread!!
Do I like my van.....I love it! Glad I took out the extended warranty though because I'm not sure how long all that emissions equipment will last?!!!
Apologies if that was long winded......I could talk a glass eye to sleep about fuel economy!!!

 

[mopardave]

further to that.......I'd say, comparing Polzeylad's van spec and mine........his is bloody good......mine's just ok.

 

[former member]

Unlike our last Cali which was AWFUL on fuel!
A guy I know runs that Rhino company!

 

[phil_n]

I've a 150 Manual Kombi.

Hardly any weight in it and get between 43-44 on the MFD. It's slightly optimistic, but I still constantly see north of 40mpg.

As for Adblue. When I collected the van it said 2500 left, 1200 miles on it's now on 3000 left!

 

[CRD]

I've a 150 Manual Kombi.

Hardly any weight in it and get between 43-44 on the MFD. It's slightly optimistic, but I still constantly see north of 40mpg.

As for Adblue. When I collected the van it said 2500 left, 1200 miles on it's now on 3000 left!

Exactly the same for me. I'm consistently getting around 550 miles per tank (70 litre, refill usually when range is getting close to zero). Takes between 60-63 litres to brim. Not sure if this difference is down to pump accuracy or MFD range estimation discrepancy, so averaging pretty consistently over 40mpg.
I'm currently on 21k miles and I think engine is loosening up nicely now.
Also getting around 4000miles to tank of Adblue taking it to 500 miles range left.

 

[RattyMcClelland]

 

[chriscroft]

Exactly the same for me. I'm consistently getting around 550 miles per tank (70 litre, refill usually when range is getting close to zero). Takes between 60-63 litres to brim. Not sure if this difference is down to pump accuracy or MFD range estimation discrepancy, so averaging pretty consistently over 40mpg.
I'm currently on 21k miles and I think engine is loosening up nicely now.
Also getting around 4000miles to tank of Adblue taking it to 500 miles range left.

40mpg at 550miles/13.65galons. That is bloody good.
On paper the 204 v 150 don't look very different in terms of economy. I'm still hoping for 30mpg

 

[mopardave]

can't see the pics ratty.

 

[TEESIXY]

My 150 manual is hovering around a genuine, calculated 40 mpg, 2-3 mpg being due to the warmer weather, it seems. About 50% of that is fully loaded too. 70 - 76 mph indicated seems to be the norm, although i sometimes give up on any ideas of progress and sit it out behind the lorries.
Cruise is good, but i think driving without can give better results at times.
I tried a big tub of Rhino additive in my previous T5, and there was no measurable improvement in mpg at all. Not saying it doesen't work but most of the success stories seem to relate to the earlier engined T4's, or did do at the time.