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Sp0oner
06-02-2009, 09:40 PM
Just realised I where I originally posted and thought I should post here just to check:

http://www.vwaudiforum.co.uk/forum/showthread.php?t=60485

Basically i'm getting 140 miles from £20 worth of fuel which works out at low 30's mpg. Trying to find the cause as no fault codes registering.

I have vag-com and only ever used it for checking fault codes. Took it to my garage today with my laptop, put vag-com on and went through some of the checks i'd never done before.

The readings for the MAF sensor were not good. The range should have been between 240 and 310 with the recommended figure being 250. The actual readings were 420+ :aargh4:

The MAF is saying loads more air is going in than actually is so chucking loads more fuel in. This would explain the poor economy and the very strong diesel smell i've been reporting for months.

Not done anything with it yet. First want to clean it, either by taking it back next week or said doing it myself with some electrical contact cleaner but i'm so useless at mechanics I don't fancy even trying to the MAF off. If it's cleaned and makes no difference then new MAF time and hope that is the answer.

Also time for me to get the vag-com manual and read it :Blush2: Also need to find out how I log in to be able to use all the functions.

Could there be other issues causing the MAF to do this or just the MAF is dirty/needs replacing?

minty0_10
06-02-2009, 11:22 PM
as for the mpg same here just, learn to live with it :(
i guess your doing more local mileage than long runs?

Sp0oner
07-02-2009, 01:49 AM
Well I hope not, that's the point with a bit of luck, that the high reading for air flow by the MAF is causing over fueling so if cleaned/replaced the fuel economy will improve.

martin1810
07-02-2009, 12:51 PM
Change the temperature sensor in case it's telling the ecu that engine is cold.

Sp0oner
07-02-2009, 01:12 PM
Thanks, it's already been replaced though so not that as that was registering an error in vag-com.