30MPG!!!!! motorway miles

[blinkyeatu]

i checked my mpg, filled then topped up and on the first 100miles i used 15L which is bloody nuts normally get low 40s around towns and B roads. shortly after my pump went pop, but taken that apart and fixed, sounds rough and smells of diesel bad.
tracking is slightly out but not that bad
its does also need a service (will do it when i get home)
also put a bottle of injector cleaner which normally does positive things.
point is any thoughts on mpg? anything i can do to sort it for return journey

[Dum-Dum]

Timing out could explain the bad noise and poor economy.

[blinkyeatu]

hmmm this is what i was thinking, but for the last month ive been fine tuning the timing using boost/performance and get it better than before till about 30mile before it popped. noise suggests advanced, smoke suggests retarded, performance suggest perfect. is it possible that airs got trapped cause it sounds like one of the injectors isn't firing right

[anto]

What speed were ya doing on the motorway?
There will be a fair bit of difference in fuel economy if you were doing 60mph compared to 80mph.

[Ruan]

Check for boost leaks - made a massive difference to how much fuel mine consumed if I had one.

[blinkyeatu]

im thinking it was a combination of things incl not driving economically, i feel it was mainly due to the tracking on my front right being way out which i hugely underestimated having that much of an effect. car was boosting fine there wasnt any fuel leaks at that point and timing was pretty close.
but cheers for the replies guys

[powerandtorque]

I'd be surprised if the tracking being out would cause you to drop to 30mpg odd on a diesel.

To generate enough resistance to impact the economy that much I would expect the tracking to need to be so far out the car was almost undriveable and certainly for the front tyres to be utterly decimated by the resulting scrubbing/dragging.

[blinkyeatu]

hmmmmm i dont think theres anything particularly wrong with my car although it did only average 40 odd although i did sort the tracking after the first 100 mile.
i think the car mainly needs a bloody good service, the max fuelling being turned down abit cause it seems abit retarded and advanced at the same time (not sure if thats even possible) also would like to put the hdi box on. any other tips to claw back any ever so important MPGs. cheers guys

[Danaidh]

i just done a run to wales from Ayr in scotland with a stop off in York i filled my tank at £70 drove 173 miles easy driving about70-80mph the whole way and it only took £23.27 to refill the tank

[blinkyeatu]

to be fair ive been doing the calculations and i dont think it came out to bad, like 40 odd mpg and it was a pretty all round trip. according to parkers average is 42, which is bit saddening after having a hdi