Fuel Economy - Xantia 1.9TD R Reg

Taffyrhys · Unread post by **Taffyrhys** » 01 Jul 2011, 13:39

I've had my Xantia for 2 1/2 years and it coming up to 170k but i've always been disappointed with the diesel fuel economy compared to other diesel cars i've owned.
I always carry out my own servicing at regular intervals, the car runs fine and i don't even drive fast or boot it and still only return 38 mpg

which is a mixture of motorway driving and rural /urban so i would expect at least 45mpg.
I've replaced all the filters but has anybody got any ideas if there is something i should check to improve the fuel economy.
Cheers
Taffy

Unread post by **Peter.N.** » 01 Jul 2011, 19:05

Hi Taffy

When the Xantia came out as a replacement for the BX there were numerous complaints about the fuel consumption the main difference being that the Xantia is much heavier. 45 mpg would be as much as I would expect doing mostly rural or motorway journeys and driving very gently.

I get around 45 mpg from my XMs but that is driving at 60 mph on motorways and never accelerating hard, keeping in the highest possible gear, braking only when essential and rarely exceeding 2000 rpm. Driven in this style it will exceed 50 mpg on long journeys, the 1.9 engine won't pull at the same low revs.

I suspect if you drove very carefully you would get 45 mpg but its driving in traffic that really kills the consumption. Try doing a steady 60 mph on the motorway or other good roads for a fair journey and test it again.

Peter

rory_perrett · Unread post by **rory_perrett** » 01 Jul 2011, 19:07

38 sounds low, our 1.9td did 39 mpg when my other half used the car to commute 10 miles through city traffic. When I used it for my 27 mile motorway/ fast A road commute it did 48 mpg. Funnily enough, driving it gentle all the time doesn't help a good italian tune-up every once in a while helps clear soot out of the exhaust system. Does yours have a Cat?

Unread post by **citroenxm** » 01 Jul 2011, 20:45

On an R plate S1 or S2 as they are the change over Id expect that too, as the later the car the heavier, the more work the ole XUD has to do to move the more fuel used..

Ive always had around the 40 mark from Early L reg Xantias, so 38 mpg would be ok for around own...

The Xantia XUD is NOT the most ecomonical... though EARLY S1 XM's with the 12v 2.1 TD units can do around 45 - 50 mpg... but later ones with Cats and more weight drop down to around 40 to 45 mpg..

Paul

Unread post by **RichardW** » 01 Jul 2011, 20:57

I did 110k in 2 Xantia 1.9TDs and averaged pretty close on 40mpg the whole time

Unread post by **Old-Guy** » 02 Jul 2011, 23:21

I get around 42mpg from our N reg 1.9 estate with an apparently similar mix of driving. With the big increase in fuel prices, I have found that going a dropping motorway cruising speed by about 5 mph to an indicated 75 produces about a 10% improvement in fuel consumption.

Has the engine undertray been discarded? It was there for several reasons one being improved fuel economy.

Do you buy supermarket fuel? If so, try some diesel fuel system cleaner and then switch to a brand that includes fuel detergents in the blend (Shell, BP, Esso).

redzzed · Unread post by **redzzed** » 04 Jul 2011, 22:07

errrm , i got a R reg 1.9td sx a/c (ac doesnt work)
and i get about 41-45 mpg having replaced fuel and air filters , and often running on cooking oil .

problem is determining how much i do get to the gallon 'cos the fuel warning light comes on when there is about 7 (seven) litres left , which is about 60 odd miles .A few times the fuel low warning light has gone OFF 20 miles later , and then on again a few miles later .
Correct tyre pressure also helps .
i also ran an injector cleaner thru it , and it 'pinks' in first now , can't remember if it did before .

mine is red , i did hear the red ones are more economical

davek-uk · Unread post by **davek-uk** » 05 Jul 2011, 08:53

My R-reg Series 1 returns an average of 40mpg on veg or 42mpg on diesel – she’s been pretty consistant over the last 100K-odd miles. And I cane her to death sometimes.

One bit of advice I'd give is to try a pump tune - plenty of details in this site's history. This gives the benefit of better low down power and it will transform your XUD! Usually it will give you better performance, to give a much more pleasureable drive, and better fuel economy too – everyone’s a winner!

Dave

wotwot · Unread post by **wotwot** » 06 Jul 2011, 11:59

My TD 96 N plate 194.000 miles known as "scabby"wont go into that!!! gives 42mpg as well,
and it does'nt seem to change if i'm wringing its neck or just cruising the motorway at 73 mph.
Did'nt know they could be diy tuned, now I'll have to troll the site to find info wont I

.
Maybe I can get it upto 110 bhp and start beating the hdi boys

.

edit mine is also the slightly lardy estate model.

Xaccers · Unread post by **Xaccers** » 06 Jul 2011, 12:34

wotwot wrote:My TD 96 N plate 194.000 miles known as "scabby"wont go into that!!! gives 42mpg as well,
and it does'nt seem to change if i'm wringing its neck or just cruising the motorway at 73 mph.
Did'nt know they could be diy tuned, now I'll have to troll the site to find info wont I .
Maybe I can get it upto 110 bhp and start beating the hdi boys .

edit mine is also the slightly lardy estate model.

Pop the cap off the top of the UFO on the pump, release the lock nut, turn the T27 (I think) fun screw clockwise 2 or 3 turns, tighten up, put dust cap back on, and go for a drive

If it's too smokey, turn the fun screw anti-clockwise a bit.

wotwot · Unread post by **wotwot** » 06 Jul 2011, 12:38

I was expecting something a little more complicated than that

.
I just had a quick look on the 306 site and its possible to get them upto 130bhp

.
Dont think "scabby" would like all that extra power,probably start to throw rods out the side of the block

.

Xaccers · Unread post by **Xaccers** » 06 Jul 2011, 17:35

The fun screw adjusts the on boost fueling, giving a bit more boost.
There's things you can do with the max fuel screw etc as details on the 306 sites, but so far I've just played with the fun screw and tweaked the turbo's wastegate a little bit (it needs a bit more).