i have a 2004 vrs and i think i have a maf issue,i have read various threads relating to poor fuel economy etc,and they all mention the maf sensor to one degree or another.my fuel consumption is hit and miss,some days it is good and other days it is poor,at the moment i am struggling to get 50mpg on a 21 mile daily commute of dual carriageway and 'A' roads.i generally fill up at the same station,but recently went over to tesco just to collect clubcard points but was finding that the range i was getting out of a tank was poor so i decided to use BP which has been good in the past but this last tank the gauge started to move after i had covered 44 miles,whereas normally i would get over a 100 miles and even 150 miles if i brim the tank.i have no warning lights and no excessive black smoke and performance is ok,does anybody think it could be the maf sensor faulty or does anybody have any ideas as to what it could be,should i get a engine warning light on if the MAF is faulty?.look forward to your replies.

Edited 16 December, 201114 yr by Jasons

i have a 2004 vrs and i think i have a maf issue,i have read various threads relating to poor fuel economy etc,and they all mention the maf sensor to one degree or another.my fuel consumption is hit and miss,some days it is good and other days it is poor,at the moment i am struggling to get 50mpg on a 21 mile daily commute of dual carriageway and 'A' roads.i generally fill up at the same station,but recently went over to tesco just to collect clubcard points but was finding that the range i was getting out of a tank was poor so i decided to use BP which has been good in the past but this last tank the gauge started to move after i had covered 44 miles,whereas normally i would get over a 100 miles and even 150 miles if i brim the tank.i have no warning lights and no excessive black smoke and performance is ok,does anybody think it could be the maf sensor faulty or does anybody have any ideas as to what it could be,should i get a engine warning light on if the MAF is faulty?.look forward to your replies.

I am having the same problem as you, I have used only Shell diesel now for 12 months.

Well a week ago on the Monday I filled up the car and by Saturday it was about 60 miles left in the tank after driving 250 miles. In the summer if I fill it right up it takes 100 miles even for the needle to move, so at least 450 miles on a full tank summer. Last night before I locked the car up I revved it up to see if I could hear anything not right, all seemed ok. This morning I started early so the roads was quiet so I turned off everything apart from the lights and cruised down the road for a mile and half in 5th gear like I do in the summer before I have to really press the brakes, in summer the trip computer says 110+mpg and today it read 100mpg so not to bad.

i have a 2004 vrs and i think i have a maf issue,i have read various threads relating to poor fuel economy etc,and they all mention the maf sensor to one degree or another.my fuel consumption is hit and miss,some days it is good and other days it is poor,at the moment i am struggling to get 50mpg on a 21 mile daily commute of dual carriageway and 'A' roads.i generally fill up at the same station,but recently went over to tesco just to collect clubcard points but was finding that the range i was getting out of a tank was poor so i decided to use BP which has been good in the past but this last tank the gauge started to move after i had covered 44 miles,whereas normally i would get over a 100 miles and even 150 miles if i brim the tank.i have no warning lights and no excessive black smoke and performance is ok,does anybody think it could be the maf sensor faulty or does anybody have any ideas as to what it could be,should i get a engine warning light on if the MAF is faulty?.look forward to your replies.

I am having the same problem as you, I have used only Shell diesel now for 12 months.

Well a week ago on the Monday I filled up the car and by Saturday it was about 60 miles left in the tank after driving 250 miles. In the summer if I fill it right up it takes 100 miles even for the needle to move, so at least 450 miles on a full tank summer. Last night before I locked the car up I revved it up to see if I could hear anything not right, all seemed ok. This morning I started early so the roads was quiet so I turned off everything apart from the lights and cruised down the road for a mile and half in 5th gear like I do in the summer before I have to really press the brakes, in summer the trip computer says 110+mpg and today it read 100mpg so not to bad.

Nobody got any opinions then or advice,64 people have viewed this and only 1 comment,c'mon people where are you when someone needs some good old fashioned advice,I know maybe it isn't an interesting post I am not modifying the hell out of my car it is just an honest example un modified etc,but I would like some input please,I would imagine most people on here browse the forum because they have a problem and would need some advice and are looking for a solution to there problem.if I get it sorted I would post the solution to help others out,which is what we are all here for.many thanks to bradfordfabia for his reply.

I thought my MAF might be dead/dying.

Advice to test it was to unplug it, and see if there's any improvement. That might have only been for running issues though, as it made it reeeeeeally slow - maybe 20-30 seconds to do 30-60mph!

You can log the values that the MAF is reading, and compare them to a good one to see how healthy yours is, but you'll need VCDS for that.

Your 21 mile commute vs my old 15 mile commute...

I could just get the MPG above 47-48 by the end of the journey, so I'd say you're doing OK with it.

A couple of things to try...

The "cage" mod. Google it or search for it here or or TDIclub. Unplug the MAF electric connector and coat the connectors in silicone dielectric grease. Then plug it back in. Get the grease from Maplin or similar.

When was your air filter last changed? Service schedule changes it every 40K which is too long IMO.

Other than the above, I found driving smoothly, anticipating slowdowns/braking and using engine braking more helped. Plus driving around under 2Krpm helped a lot with the fuel. M25 meant I didn't really get much above 60-65MPH most days which also helped.

J.

to try and guage anything by how soon the needle moves is a wast of time unless you've done a ventectomy, if your fuel and air filters have done more than 20 K start by changing them(don't leave it to the garage) then try unpluging the maf as above if thins improve try a new one, if not I would look next at the egr valve/manifold, best of luck keep us posted

Dont forget we are now running on winter diesel (more antifreeze) so that will dint your mpg a little. Mine is definitely less economical at the moment and ive put it down to that.

just an update,on my way home from work on friday i gave the old girl an italian tune up,and then brimmed the tank as it was on half a tank with normal BP diesel,so far i have covered 100 miles,gauge hasnt moved,still only getting 50mpg on the way to work today,but the miles left in tank display is showing 480 miles,i know it isnt accurate but hopefully should see 550 out of this tank so maybe i need to stretch her legs a bit more often and maybe it is the winter fuel as well.will keep you posted on anymore developments.

Well as promised I would keep you posted on anymore developments,well fuel consumption still not great,have been ummming and aaarrrgghhhing over whether to get a new mag sensor well yesterday I bit the bullet and reserved one at my local eurocar parts depot using the Brisky discount.fitted it this morning and took it for a quick run,on my normal commute of 21 miles I only manage about 53 mpg and on my 13 mile run today I achieved 55 mpg so hopefully should achieve late 50's maybe early 60's tomorrow,I think it was worth a punt.