P38A Mileage Query

oakey said:

Why has mine suddenly dropped to 15 ish tho?
Puzzling

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check tyre pressure, when was the gearbox oild and filter last done.. diff oil ?

anything that gives resistance through the transmission and drivetrain will affect efficiency. as will the gold bars in your boot

Gearbox oil hasnt been done for a while I admit, well about 60k
Same for diffs
Gold bars were eaten last week

I seem to recall reading somewhere that the average is a rolling average over a set number of miles so if it was doing predominantly long journeys then over the limited averaging miles is now into the short journeys, that could explain the sudden drop.
On mine, the readout gives around 17 on crappy hillly Czech roads and is actually doing about 15.5 when measured.
On the long motorway run mainly at 80mph the readout is just over 20 but actual is about 22mpg.
You need to do a brim to brim at same time as a reset before you start panicking about it being wrong.
Do it before a long run then also before a period of short runs and you'll get an idea where you are then.

oakey said:

Gearbox oil hasnt been done for a while I admit, well about 60k
Same for diffs
Gold bars were eaten last week

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Diffs need to be done more often that that by far. I do mine every 10k.

Better do them over Xmas then ty Grrrrr
I have measured over short journeys and long ones inc motorway and still much lower than it has been for the previous three years.
Never done a brim to brim as not really interested in actual mpg, it is just the sudden change that is puzzling

oakey said:

Better do them over Xmas then ty Grrrrr
I have measured over short journeys and long ones inc motorway and still much lower than it has been for the previous three years.
Never done a brim to brim as not really interested in actual mpg, it is just the sudden change that is puzzling

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A binding brake is a common cause.

I thought maybe the handbrake but it seems clear
I I can figure out where it is and how, I am going to give the MAF a bit of a clean

Make sure u get the correct maf cleaner

Some people reckon brake or carb cleaner?

You can bye maf cleaners on line

I will get some methinks thank you