Mpg on a XUD

[Mike]

Hi all, my diesel seems to be drinking derv :/ im averaging 34 Mpg if im lucky.
Its got an fmic on with 2.5" boost pipes, un modded lucas, and a K&N airfilter. No exhaust mods, and it isnt driven on boost all the time, maybe once or twice a trip out just to get to the speed limit.
I topped up £20 which was about 14.5L and it lasted 112miles or around that. Trips included short runs and longish runs.
Is this normal? Or is there something amiss?
As ive never had one, im unsure of what mpg to expect..
Also, ive checked all fuel lines etc and cant find any leaks, so it really puzzles me when ive been through a couple of mpg topics and some people are getting 45+ with mods.
Thanks in advance for any help.
Mike

[4WayDiablo]

Something's up. Probably needs a good service tbh

[Mike]

Sorry forgot to add, just had a full service other than the belt, havent got round to doing that yet.

[strictly_perv]

2.5 pipes are huge! Very unnecessary and probably causing a fair amount of lag dropping MPG

[Chris_90]

Lowest mpg ive had was 32mpg I normaly advrage 37mpg all stop start round town tho

[Mike]

Ahh, well round where i live its more 30mph everywhere, few traffic lights but more 30mph and a few 40+
It could well be tuff and 34mpg'ish is what im stuck with ):

[Dale]

Wonder if there's a split in the leak off pipes or the hand primer! I'm see around 55 mpg 50 mile round trip to and from work cars saving me a fortune!

[Mike]

Hmm, will have another full look over it all tomorrow, see if i can find anything.

Wish it was saving me a fortune lol, awful knowing your old car did more mpg then a diesel haha!

[RJDubya]

I was seeing around 35-40 mpg using the car for short trips, got it doing longer trips for a few weeks and was returning 48-50 mpg, i was astounded to be honest.

Been using more water than fuel lately though...

[WiNgNuTz]

I'm having similar issues tbh mate, sometimes barely managing 30mpg over a full tank. Also no signs of a leak ANYWHERE, leak offs are fine, grenade is fine, tank seems fine. I've got a cone filter, mildly modded lucas pump, and no exhaust mods. Suffering a bit with wastegate creep at the moment though, so that's probably not helping matters.

[Mike]

I havent really done many long motorway runs so i cant say if mine would improve on longer runs
Just really bizzare why its hitting such poor mpg figures, when everything points to atleast 40-45ish+ maybe.

[spike2002]

I put £20 in mine and get 160 mile and that's ragging the tits off it :p

[Mike]

Lee shush! No need to brag lol, you've said enough already -.- haha!

[spike2002]

Stop driveing it like a grandad that's proberly what's up with it :p

[Mike]

Hahaha! Soon as boost kicks in, you can litteraly watch the diesel gauge go to empty :/

[spike2002]

Just a thought mate you got a dodgey fuel guage?

[Toms306]

Only boost once or twice a trip? Why? You want low boost to.increase efficiency and therefore mpg. Think this is why my HDi does so badly as I'm used to sitting on low boost all the time, but with the HDi (and obv the dt) low boost comes in higher up the revs so it saves fuel to drop a gear, as counterproductive as it seems! Obviously sitting on the redline won't help, but honestly if you're grannying it in 5th at 30 (i don't know dt ratios) then you're not gonna get such good mpg...

[Mike]

Hmmm dont think so, seems to work as it should, £20 takes it to just about 1/4 tank then after like 50miles its hittin the top end of the red.
Then another 50miles and its middle/bottom of the red and then its due a top up i think.. Never let it get any lower as i dont wana run outa diesel :/

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Only boost once or twice a trip? Why? You want low boost to.increase efficiency and therefore mpg. Think this is why my HDi does so badly as I'm used to sitting on low boost all the time, but with the HDi (and obv the dt) low boost comes in higher up the revs so it saves fuel to drop a gear, as counterproductive as it seems! Obviously sitting on the redline won't help, but honestly if you're grannying it in 5th at 30 (i don't know dt ratios) then you're not gonna get such good mpg...

Hmmm kinda makes sense mate, but as soon as i start boostin the gauge just pritty much goes to the red light :/
So ive tried to avoid it to see if theres any change, but so far there isnt. Boostin or not, the gauge seems to do the exact same.

[ozonehostile]

i get similar mpg figures to you mike if im just going to work and back, distance of 12 miles each way, half country roads half city so by the time i get to work its only just warmed up. on a motorway run il easily get 200 miles for my £20 of diesel

[Piggy]

My light comes on with a 15litre topup anytime I boost and go round a bend coz the tank is so big and it sloshes around.

but fyi....get a bosch!

[Toms306]

Wait...you're trusting the guage? Fill it up and see what happens!

[Mike]

i get similar mpg figures to you mike if im just going to work and back, distance of 12 miles each way, half country roads half city so by the time i get to work its only just warmed up. on a motorway run il easily get 200 miles for my £20 of diesel

Hmm maybe it is because of the short runs then as thats a very similar case with me mate, only just reaching running temp as your like 2/3mile away from where your stoppin.

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My light comes on with a 15litre topup anytime I boost and go round a bend coz the tank is so big and it sloshes around.

but fyi....get a bosch!

How long does £15 last in the red?
I usually yop up once its been im the red for like 20miles or so.
I am also planning on doing that at some point lol

[Pugmarshall]

I've done 32 miles with the light on, never had to go any further than that... That's running ~25PSi and it smokes on boost. Average I get around 45MPG.

[Mike]

I've done 32 miles with the light on, never had to go any further than that... That's running ~25PSi and it smokes on boost. Average I get around 45MPG.

Wow, knowing that, there is almost certain something wrong.
What type of journeys you do? All long or some when your arrive the cars only just got to temp?

[Piggy]

my wife when she used to use the car more has done 100miles with the light on....

[stokesy]

have same problem all standard returning between 120 to 160 on half tank 30 quid both manners of driving (granddad driving and raggin shit out of it)

[Pugmarshall]

I've done 32 miles with the light on, never had to go any further than that... That's running ~25PSi and it smokes on boost. Average I get around 45MPG.

Wow, knowing that, there is almost certain something wrong.
What type of journeys you do? All long or some when your arrive the cars only just got to temp?

Mixed really, never less than 5 miles each way as I live in the country. I do a lot of driving and tbh even when I give it death, never really gets bad on fuel.

For example; my "fun" road is a 36 mile round trip and it usually costs roughly £7, which is around 32mpg... And that's erm... "spirited" driving.

[maxlee]

cold start cable sticking maybe?

[Kwik]

i would check for boost leaks too. if you got a boost gauge plumped in check there, the intercooler d seal and jubilee clips on turbo to intercooler pipe. Boost leeaks cause poor mpg as it pumps in more fuel but losses it through the leaks. since sorting my boost leaks and with my economy mods like hdi box and retune i've seen easy 60mpg this week

[Mike]

i would check for boost leaks too. if you got a boost gauge plumped in check there, the intercooler d seal and jubilee clips on turbo to intercooler pipe. Boost leeaks cause poor mpg as it pumps in more fuel but losses it through the leaks. since sorting my boost leaks and with my economy mods like hdi box and retune i've seen easy 60mpg this week

100% no boost leaks mate, one of the first things i checked when i noticed my mpg was down, after all the fueling bits.

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cold start cable sticking maybe?

Have to say, i havent checked that! As for one, im unsure of its location lol, any help?