Diesel owners, comments on running costs/economy please.

nuttinnew · Post by **nuttinnew** » Sun Nov 21, 2004 9:46 pm

I keep thinking about getting a diesel for the economy (ideally a mk5 Colour Concept TDi

) and have pondered an engine swap with 1 .9 SDi as they're reasonably cheap and easy to get and came in a mk4 originally so fitting would be a doddle. My mk4 is an early 1.3 and it seems to average 40-45mpg which isn't bad but it has more motorway use of late than is normal for me, how would a diesel compare?
The car gets used for normal boring daily transport and gets driven with restraint.

I've been playing with some figures to try and guesstimate the difference in running costs, please tell me how wide of the mark I am

I'm assuming similar servicing, insurance and fuel-per-gallon costs, basing mileage at 10000 miles per year which seems reasonable.

1300.
Â£100 road tax
40 mpg

10000 miles at 40mpg would require 250 gallons of fuel.

At a cost of Â£3.95 per gallon (86.9p per litre) 10000 miles worth of fuel would cost Â£987.50.

1900 Diesel
Â£180 road tax
50 mpg

10000 at 50 mpg would require 200 gallons of fuel.

At Â£3.95 per gallon 10000 miles worth of fuel would cost Â£790

Whilst there is saving of almost Â£200 on fuel costs this is countered by more expensive road tax which would work out at a total saving of only around Â£10 per month...

At 60mpg the saving is around Â£20 per month but is that a realistic average figure from a 1900 diesel? Is Â£20 a month worth worrying about? If I were to pay an extra Â£20 per month it would probably cover the extra needed by a VR, of course one of those would cost more to insure and service.

All opinions and comments welcome and wanted, help me get my head round this please !

Post by **Josh_PoloGTi** » Sun Nov 21, 2004 10:42 pm

I think I'd stick with the 1.3

david burton · Post by **david burton** » Mon Nov 22, 2004 9:36 am

you're getting 45mpg and want more?!

Be happy with that, save the money, the hassle, the pain of selling it on (I wouldn't buy a conversion) and no doubt the insurance will be a little higher. I don't think you'd save in the end - things tend to be more expensive for a diesel, and components wear a bit more due to the extra weight.

HTH!

nuttinnew · Post by **nuttinnew** » Mon Nov 22, 2004 12:46 pm

david burton wrote:you're getting 45mpg and want more?!

Ah but the last couple of tankfuls have I think unrepresentative of my normal usage, they've been long motorway runs at slow speeds so the engine has been fully warmed and only subjected to light loads whereas I normally only do very short stop-start journeys where I'll be lucky if it gets off of choke; if I can get the same economy under those cicumstances I will extremely happy believe me

I also wonder though if an 'economical daily driver' is really that for the sake of an extra 10-15mpg working both ways i.e. if the savings over something that does a few less mpg isn't that great then why not get summat a bit speedier and more interesting? Hmmmm...

david burton · Post by **david burton** » Mon Nov 22, 2004 5:54 pm

That's the spirit!

get a 16v-er

for the difference - 200 quid between a diesel and 1.48v, then the 16v is about another 5-10mpg less (high twentys to high thirties)... so you're looking at about another 100 quid a year

....

definitely worth it! 30p a day

nuttinnew · Post by **nuttinnew** » Tue Nov 23, 2004 12:24 am

Is that all you can get out of a 16v?

What are they like on a run? Tbh I need to average about 40 to be able to afford a car, I don't earn a great deal. The problem with something a tad sporty in the 16v vein (i.e. thrives on revs) is I'll never end up driving it sensibly, something that's a doddle in a plodder. My previous GT could end up giving some frightening low mpg figures. Usually while harrassing Cooper Ss so I had a smile on my face and I admit Herr Schrick isn't overly concerned with economy but still...

david burton · Post by **david burton** » Tue Nov 23, 2004 12:52 pm

someone has got 45mph once, and on a motorway I've got 40mpg at 75.

but as soon as you open it up.....

KITT · Post by **KITT** » Tue Nov 23, 2004 1:35 pm

david burton wrote:for the difference - 200 quid between a diesel and 1.48v, then the 16v is about another 5-10mpg less (high twentys to high thirties)... so you're looking at about another 100 quid a year

Second the 16v option

Mine does just under 40mpg and that's on a 25 mile commute with 5miles in stop start traffic. Red line it most of the time so if I took it easy would see more. Also, running it on super unleaded seems to improve the ecconomy

david burton · Post by **david burton** » Tue Nov 23, 2004 2:12 pm

KITT - that's darn good! I should try that - does it work out better overall (i.e. pence per mile for super?)

at 80mph I get about 35mpg, never falls below 33 but I do do a lot of motorway miles. I should be getting more mpg! what's your commute like?

KITT · Post by **KITT** » Tue Nov 23, 2004 2:48 pm

I know! I only worked it out last week as I was thinking of getting a different car in the new year and wanted to know what my 16ver was doing. I fill it with ~42lt and get ~370miles to a tank. There's a handy converter here:

http://cheekyink.co.uk/mpg/MPGCalculator.htm

My commute's mainly along the A38 into Bristol with heavy traffic the closer to Bristol you get, where it turns to stop/start for about 5 miles. There a few miles of country roads too near my house where I like to give it some beans

I can honestly say I don't drive it economically and tend to hold onto the gears when accelerating. I recon 450 out of tank could be possible with careful granny driving

The super unleaded made a little difference but not really that much to be honest. It has helped with the pinking I some times got going up hills in the morning. Also seems to have given it a little more go at the top of the rev range >4500rpm

david burton · Post by **david burton** » Tue Nov 23, 2004 3:52 pm

So how much extra mpg did you notice with super? You'd have to get about 8% more mpg for it to be worth it (on costs alone)

do a proper check - fill to the brim, then fill to the brim when you come to refill it.... I'm curious / jealous!

KITT · Post by **KITT** » Tue Nov 23, 2004 4:13 pm

david burton wrote:So how much extra mpg did you notice with super? You'd have to get about 8% more mpg for it to be worth it (on costs alone)

do a proper check - fill to the brim, then fill to the brim when you come to refill it.... I'm curious / jealous!

I doubt it was as much as 8% to be honest but I am getting a very consistant 40mpg

I always reset the trip when I fill up, always put between 40-43lt into the tank and get between 360-380miles out of it. When I first got the car I used standard unleaded and got over 400 miles usually. Then it dropped to under 400miles at which point I switched to super unleaded. Initally, it went back over 400miles but then steadily decreased as the traffic's got heavier these days

.

It's been doing 40mpg for the last 6 months so I think it's settled now

I should add the car had only done 1200 miles (owned by some old dear) when I got it just over a year ago and since then I've added 14000 miles.

srbpower · Post by **srbpower** » Wed Nov 24, 2004 6:34 pm

I run our polo on super and I think it did around the 375 mark on a full tank (So full no more fuel would go in

). But a least half was town driving. Have been quite shocked at how good the 1.4 16V is on fuel. I was expecting quite a bit less. Spose she does drive like a girl

I did notice a big difference after it was treated to full filter, plugs, belts and oil change. Plus the fuel line were flushed though.

Anyway I don't know what you are all moaning about my car has just managed just over 150 miles on 45 quid of super

Si

KITT · Post by **KITT** » Thu Nov 25, 2004 9:36 am

srbpower wrote:Anyway I don't know what you are all moaning about my car has just managed just over 150 miles on 45 quid of super

That makes my other car look positively green!!

Average 20mpg, dropping to single figures on track

What you got to better twin Webers then?

srbpower · Post by **srbpower** » Thu Nov 25, 2004 10:20 am

SR20 with nice not turbo popping flames all day

Nice car by the way, been in a carbon bodied one with a hyabusa (spelling? ) engine

They are just so much fun

Si