Better Fuel Consumption
 

For many months despite carbon cleaning, service including all filters the average fuel return was 29.5 mpg in my 75 diesel saloon automatic. Tried the performance diesel fuel in the last two tanks and noted the return with no change to driving conditions or driving style and wow now getting 37.5 first tank and second tank 37.8 , this has to be better for the engine and environment.
Enjoyment factor 10 and more smiles per mile.

A 27% economy improvement just by swapping fuel?
Staggered!

That partially seized back brake must have freed itself.---:D:D:D

Y'all know I'm a sucker for experimenting with MPG in the CDTi engine, so this evening, seeing as I had only 15 miles range left, I brimmed the tank with BP ultimate diesel and set all my tyre pressures to 34PSI.

So far I've not seen a great increase in fuel economy - I took the car along the A14 roadworks just outside Cambridge, a total of 27 miles at an enforced 40 MPH and got an indicated 70.6 MPG over that distance. That's about normal.

Before anyone jumps in - I know it's only an indicated figure and not necessarily accurate but it's about what I usually get on that journey.

I'm about to take the Tourer on a bit of a road trip so will hopefully be able to report back as to whether it's made any difference by the time I've got some miles behind me.

I logged every single litre of fuel that went into my CDT auto tourer over the 12 years that I owned it.
It generally ran on Tesco's Finest (cheapest) but I did try other fuels including the Premium diesels.
They all returned the same mpg, give or take.

Which is a 27% increase in mpg.

I'd be amazed if anyone could get a 1-2% improvement from a variation in fuel 'qualty'. Sorry, but something else has caused it.



TC

Only press one pedal at a time is my advice ;)

The big one on the left should not be used in conjunction with the small one on the right, if fuel consumption is a concern.

As an aside, my 1800 saloon, was indicating 42MPG today.......awesome :drool4:

Brian :D

My aim is not to use the big one on the left at all if I can help it.
Anticipate and slow down naturally if possible.
Boring, I know.

Better fuel consumption
 

Following the two tanks of premium diesel returning 37mpg, the tank is now filled with Morrisons diesel with a trip meter set to zero, same driving style lets see if the fuel consumption changes.
I shall get a diesel emissions report next week. Our works van a 1.3cdti Vauxhall returns 52mpg might try the same tests.

Nice one Frostie !!! :bowdown::bowdown:

38.8 on my CDTI Auto.

Hi all,

As a "newbie" I dont want to get on anyone's wrong side.
I've only just bought my ZT Cdti. But,
As to fuel economy goes I'm used to driving my MG ZS 120 ( read 135bhp Tf engine fitted ) petrol.
I've had a re-map and taking it nice and steady I've twice cracked 50mpg.
Thats not what any computer has said, but what I've accurately worked out by the good old fashion fill the tank, drive, refill at the same filling station and at the same pump!
I had my re-map done at K-Maps.
Not sure if they do diesel cars, but if anyone has a petrol I would recommend them!
This is using Morrisons finest!
K - maps take the 135bhp petrol and get very close to 150 bhp. Power, torque and economy ( if you drive sensible ) all go up.

K series, rubbish engine who would want one of those :getmecoat:

On saying that.........me every time, and 47MPG was easily obtainable in a 200BHP ZS 1800T, as of course was sub 20MPG if enjoyed :drool4:

The truth of the matter is simple, fuel consumption of the 75 and ZT models should not be a major factor in the overall enjoyment or otherwise of the car.

If fuel consumption is of a huge concern, then chances are you will not enjoy ownership.

In reaction to the original gist of the post stating the decrease in fuel consumption in regards to the type of fuel used..........well I'm going to say one thing about that, and improvement of the magnitude being claimed in relation to fuel quality is absolute nonsense,

Brian :D

this is based on what?
I can tell you quite categorically that a 10% improvement by switching fuel is impossible. The calorific value of Diesel fuel virtually almost constant throughout the range irrespective of make. That is where you energy comes from.

There is simply no way you can get this improvement by switching fuel.

I think maybe bsabantam has got the message by now, but it will still be interesting to see what he comes back with when he has completed his current mpg test.

Very little change, I suspect.

Using premium fuels can give advantages, long term, with the additives used.
Swapping from one tank to another will not prove anything.

It is a bit like a fat bloke eating a salad for one day, and then jumping on the scales to measure the difference. ;)

I'm shocked! :eek:

I wont get into an argument about the K series right now, but I understand what you're saying about worrying about mpg and spoiling the R75 / ZT experience.
I'm thoroughly enjoying my purchase!

It is nice to have your cake and eat it sometimes though. :D

Nice analogy...😬



Sent from my iPhone using Tapatalk

Definitely tongue in cheek, I think the K series is a fantastic engine, I own five cars with k series fitted, and the only 75 I've ever bought because it was exactly what I wanted was an 1800T ;)

Brian :D

We all know you love the old oil burners :D:eek:

It is such a shame that they didn't make a V8 diesel with an auto box. :drool4:

:D

I was actually looking for a good example of a 1.8 T but had heard mixed things on towing, which is why I bought the diesel.

pretty close, 36-38 on my Dizzle Auto :D now


Was down in low 30's before i did an inject leak test and sort out just 1 injector .

You did absolutely the right thing.----:bowdown:

2.o cdti auto fuel consumption
 

Following a tank of standard supermarket diesel the fuel consumption went back to 32.56 mpg, I exhausted the tank and filled up with esso performance diesel and went on a run from Wolverhampton to Exeter and from Wolverhampton to Bath and normal average driving and the returns are as follows first tank 41.43 mpg and second tank 42.97 mpg.
Esso super diesel is working for me although more expensive the benefits far outweigh the disadvantages of running supermarket fuel, I know the additives in the Esso fuel are working as I have proof and have checked for brake binding and know all the filters were changed at the last service.
Ownership and enjoyment are great knowing that I can get a decent return on fuel economy.
Mot due next month, I will be flushing engine with BG power restorer and adding the diesel fuel treatment to keep the engine performing as it should.
The engine has now covered 99000 miles and used very little oil as yet.
Just need to improve the radio reception to the aftermarket multi media nav system, its wired through the existing antenna plug, Ive tried a booster aerial and this was even worse.

...... and there is your answer! (that 42ish mpg is what I would get over a 100 mile run with no consideration on economy - regular maxol fuel - I am not a fan of supermarket fuel, the maxol will give me very roughly 3% increase in range in my 'normal use')

do a like for like test, with a brim to brim :getmecoat: Or at the very least, compare running it for a period of one year with one fuel and a second year with another. Use maths and not the IPK

Oh you do, do you?:D

check the connection on the rear window. Possibly failed aerial amplier fitted to window pillar (cannot remember which one I am afraid). A booster will only 'boost' the interference.

I measure tank to tank. Set the trip and off I go.

At the moment showing 53 mpg from my diesel.

Worst ever 49 mpg.

I use any diesel. The nearest garage when I need to fill up.

Never let the tank go below 1/2 full.

The vast variations by the OP leave me baffled.--:shrug:

What ARE these additives that can give another 10 mpg.

I definitely want some.----:D:D:D

;)

https://i.pinimg.com/originals/ac/5c...390ef171f5.jpg

:wot:
That's a very good question Jon but the answer would, of course, be a closely guarded secret. I wonder why the oil companies concerned don't exploit this remarkable achievement in their advertising? ;)

Simon

I really enjoyed CLF's post. ( great way to save fuel.-;)--)


Also your tongue-in-cheek answer that will probably go over the heads of lots of folk.---:bowdown:

"give or take" ...


Good advice - better advice from an mpg pov is get a car with 3 pedals...

That'll likely also return a similar mpg - until everything is clogged up again... :getmecoat:

Couldn't agree more.

My own experience has been mostly with Shell ultimate (other premium fuel brands are available but with no guarantee of performing the same). On my regular commute (26 miles each way - same traffic each week, different weather). Running mostly premium fuel but occasionally sainsburys fuel. Consistently worse mpg (2 - 4 mpg) and didn't always run as smoothly. Never once did the Sainsbury fuel give better mpg than the Shell ultimate. And that is over 7+ years. Calculating the extra fuel cost against mpg also came out comparable in pence per mile most of the time as well. So for me it's proven that paying more for fuel doesn't have to mean a higher cost per mile.