VW Goilf estate 19.l TDI with ATD engine

[Mrcheerful]

Stephen H wrote:
> Hi all,
>
> The miles per gallon figure has dropped by 20%.
>
> Ive checked for fuel leaks (none) and replaced the air, fuel and oil
> filters and changed the oil.
>
> The Car passed its emissions test at its MoT only 2 weeks ago (I've
> had the problem a month now)
>
> What else would cause a sudden and permanent drop of MPG?
>
> I'm now getting 400 miles per tankful instead of 500 miles per
> tankful. I can usually get 50 litres in a tankful.
>
> Stephen

What did you do a month ago.

[Mrcheerful]

Stephen H wrote:
> On 05/07/2012 10:28, Mrcheerful wrote:
>> Stephen H wrote:
>>> Hi all,
>>>
>>> The miles per gallon figure has dropped by 20%.
>>>
>>> Ive checked for fuel leaks (none) and replaced the air, fuel and oil
>>> filters and changed the oil.
>>>
>>> The Car passed its emissions test at its MoT only 2 weeks ago (I've
>>> had the problem a month now)
>>>
>>> What else would cause a sudden and permanent drop of MPG?
>>>
>>> I'm now getting 400 miles per tankful instead of 500 miles per
>>> tankful. I can usually get 50 litres in a tankful.
>>>
>>> Stephen
>>
>> What did you do a month ago.
>>
>>
>
>
> absolutely nothing....
>
>
> it is only in the past fortnight I have had 4 new tyres, (previous
> four were at legal limit) a MoT pass, an EOBD reader check for
> current and pending faults, (none found) new air/oil/fuel filters and
> oil change, and no evidence of any diesel leaks.
>
> and the poor MPG problem persists....

were the tyres the same dimensions as the old? and was the tracking done
correctly? If the tyres were a little different it will upset the miles
recorded, wrong tracking can increase drag.