help disco doing 20mpg

hi all i bought a 300tdi with blown head gasket.had the head checked and skimmed and top end rebuilt.de-catted it and blanked egr valve off.the tank was empty so i put a gallon in it and ran it out to check the mpg to find to my horror im doing 20mpg and slow getting over 70 any ideas plz.im running standard 235/75/16 tyres no rooof rack it does have a 2" lift on it and the pump is in origanal possition

Not how to measure mpg half that gallon could still be in the tank the only true way is to fill it to the top drive round for a few days then refill to the top and take note of how many litres it took to refill work out your mpg from that number

thats down to empty tank i took sender out in the begining to see what was in there and it was empty and did the same afterwards.plus the other problem of getting to 70 pretty quick but will not go over 75 unless on a long run with foot to floor

Are you getting 20 mpg on long runs or short round town trips? You should get around 25-30 on a run but for short journeys in the cold weather 20 sounds normal .

I dont get much more than that round town so wouldn't worry too much.

20 mpg sounds perfectly normal. OK the low side of normal, but not any great surprise.

Man up mines on 18

Dr_evil said:

Man up mines on 18

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Yeah, but you'm speshul

Dartmoor Navigator said:

Yeah, but you'm speshul

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I'm not that speshul

Dr_evil said:

I'm not that speshul

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Oh, OK then

well i dont a 115 mile round trip from torquay to liskard back home again and it cost 50 quid somehow i think im right in saying somethings wrong somewhere

Well thats about 35 ltrs for fifty quid and you did 115 miles so that works out about.................15 mpg They do say the lift will cause more drag but that still seems excessive. Have you checked the brakes aren,t binding ?

mudrunnerv8 said:

well i dont a 115 mile round trip from torquay to liskard back home again and it cost 50 quid somehow i think im right in saying somethings wrong somewhere

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I do a 125 mile round trip to work every week in my 300tdi auto,half of which is on single cariageway and half dual cariageway and I put £40 worth of fuel in,so your not too far off.

It won't help if you're trying to do 70-75 all the time, Mine doesn't even do that without a big hill

I manage around 100 miles to a 1/4 tank or so.

i managed to get 83 miles out of a quarter of a tank it is now down to 13mpg somethink in majorly wrong and if people a5re getting gthe same theres something wrong there aswell my last disco did 28-32 depending if round town or motorway.so going to chec k the turbo and the injection pump this week so any other ideas on what to check or change out would be handy

mudrunnerv8 said:

i managed to get 83 miles out of a quarter of a tank it is now down to 13mpg somethink in majorly wrong and if people a5re getting gthe same theres something wrong there aswell my last disco did 28-32 depending if round town or motorway.so going to chec k the turbo and the injection pump this week so any other ideas on what to check or change out would be handy

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i told ya £300 !!

If the tank was empty and you ran it until it stopped then there will be fuel in the tank now . You never get it all out . My 300 auto does 28 / 32 mpg 60/40 cooking oil

my 300 is ifted 2" and running 33"/12.5"/r15 tyres with lightbar and snorkel, and i'm still getting 29-30 mpg. It was down at 24mpg and slow, replaced the lift pump as it was leaking into the engine oil. Now its up on power and using less fuel

when was the last time i was serviced? oil, filters ect.. if it was a while back.. a good new service kit will often raise your mpg!