mpg from a 150

[Anthony]

Yes its mapped. If I didn't get 50+ on the motorway Id be looking for why?

I'm on a mission at the moment to find out why its not that good, i only use shell fuel and filled up with v power yesterday to see if thats any better, am on with cruise control to see if that helps , run injector cleaner through. The injectors were sent off to be checked at a specialist when the cam was replaced 18 months ago and were fine . And ive got the innotek turbo cleaner to do in the next couple of weeks . so I'm fast running out of ideas lol . also no faults stored on the ecu either, and i'm trying to drive like a grandma

[Defender]

pretty good its amazing lol ive just done the egr and inlet + oil n filter. and fitted a new gen maf, and still only manage 35mpg round town and 44.1 was my best on the motorway for 2 hours yesterday at 70/80 !

Ouch thats not right! 35 around town (depending on driving style obviously  ) is about right but 44 on the motorway!!! I get around 52 on the way to work at 70/80 as get stuck in traffic and usually around 60 on the way home although I usually keep it below 60mph for the return.
Have you checked for a boost leak? May also be worth plugging it in and checking the N75 valve.

[Anthony]

all the pipe work looks to be ok and i replaced the lower ones both sides as there was a very minor oil leak from one side. Ive had it plugged in today at work and apart from the airbag light being on from me fitting cruise control on sat all was in order. would a faulty n75 show as a fault ?

[Defender]

Yes it would flag up a fault....very strange indeed!

Hope you cure the problem I will be interested to know what it is.

[Steve_PD]

N75 doesn't necessarily  show up as a fault but would give ou boost problems/overboost rather than mpg problems.
Have you ever logged the maf?

[Anthony]

what would i see from boost problems ?  if i go uphill in say 3rd or 4th steadily   it coughs a bit as as the turbo comes in at about 2 k ish but its fine if i gun it . as for logging the maf i dont even know what you mean  I know ive made comments like useing the diagnostic machine at work , but i'm only a painter lol

http://uk-mkivs.net/forums/t/399759.aspx?PageIndex=3   Ive seen this off google

[Anthony]

I did clear this fault on sat,17667 p1259 engine coolant system valve short to ground , cant seem to find what its from tho.
I'm sure ive read somwhere that the coolant temperature can cause problems , if its on the way out.

[Anthony]

coolant temperature sensor even ^^