Mpg.

[katman]

declining mpg was the earliest sign that our maf was degrading - I thought you had changed yours recently - was it a new one?

 

This thing about MAFs still confuses me a bit.

 

I have read posts that say people have unpluged it and got a dramatic improvement in performance.

 

Is it only diesels that are badly affected or does it also apply to Petrol models ? Mine is a 2.0 petrol

 

If the MAF is OK what happens if you unplug it.... does performance get worse ?

 

I tend not to drive my Galaxy "hard" but I did try unplugging the MAF one day and going for a burn down the dual carriageway. Coming back the other way I plugged it back in. I didnt really notice any difference in performance one way or the other.

 

Does that mean the MAF is OK or should there have been a noticable difference eg

 

MAF knackered = runs better unplugged

MAF OK = runs worse unplugged

 

Does no difference indicate that it is on the way out ?

 

Thanks

 

Keith

[NikpV]

declining mpg was the earliest sign that our maf was degrading - I thought you had changed yours recently - was it a new one?

 

This thing about MAFs still confuses me a bit.

 

I have read posts that say people have unpluged it and got a dramatic improvement in performance.

 

Is it only diesels that are badly affected or does it also apply to Petrol models ? Mine is a 2.0 petrol

 

If the MAF is OK what happens if you unplug it.... does performance get worse ?

 

I tend not to drive my Galaxy "hard" but I did try unplugging the MAF one day and going for a burn down the dual carriageway. Coming back the other way I plugged it back in. I didnt really notice any difference in performance one way or the other.

 

Does that mean the MAF is OK or should there have been a noticable difference eg

 

MAF knackered = runs better unplugged

MAF OK = runs worse unplugged

 

Does no difference indicate that it is on the way out ?

 

Thanks

 

Keith

 

 

It seems that the thick film sensor used degrades over time - so at some point I would guess that it would make no difference - but perhaps its so far out of spec that the ecu doesn't believe it anymore :35: and uses a default value whether its connected or not :P

 

Makes a big difference on diesel engines not sure about petrol variants though

[Scorpiorefugee]

Just a quick reply about the MAF. I replaced mine recenty as I finally accepted that the old one was kaput. Preformance improved dramatically and the fuel consumption increased also, probably because it took time to adjust my driving habits. Fuel consumption is still a bit heavy but I can live with it.

 

And finally, just to complete the comparative figures which I left at "down to the 1/4 mark", I recently got home in the early hours having started home on a 200 mile trip showing 530 miles with a shade over 1/4 tank left. Next morning it was a bit reluctant to start so I hot footed to the fuel station and put in

[Bigjeeze]

Just a quick reply about the MAF. I replaced mine recenty as I finally accepted that the old one was kaput. Preformance improved dramatically and the fuel consumption increased also, probably because it took time to adjust my driving habits. Fuel consumption is still a bit heavy but I can live with it.

 

And finally, just to complete the comparative figures which I left at "down to the 1/4 mark", I recently got home in the early hours having started home on a 200 mile trip showing 530 miles with a shade over 1/4 tank left. Next morning it was a bit reluctant to start so I hot footed to the fuel station and put in

[NikpV]

I thought it mean't - thus it has been demonstrated

 

but I was too young to have studied latin at school BJ :unsure: :angry:

[sanjsanj]

 

Our 115 Ghia is more thirsty than the old 110 which is the workhorse. I struggle to get much more than 42/43 out of the 115 although I have managed 50 on a couple of occasions.

 

I find that the old 110, without a computer, settles at around 45/46 driving to the speed limits and I know that, from a full tank, I can get 100 miles down to the full mark, 250 down to the 3/4 and 400 - 420 to 1/2 and 550 - 570 down to 1/4.

 

The truth is known when I top it up because I recon to get 10 miles to the litre. So, fill it up, use it for a bit, divide miles by 10 and if that's what it takes to fill it up, I,m happy.

 

Ron.

 

I am looking to buy a 115 model with auto trans. The reason i am buying it is that it has 5 gears. my current gal has 4 gears. With the extra gear added in conjunction with the previous 4 gears, surely the revs should come down and therefore the MPG it gives be much more that compared to the old 110 model.

 

I mean its just like having a manual 5 gear gal and then the manufacturer suddenly realises that an extra gear = lower revs which= more mpg (which by the way i could have told you when i was 5)...which is what they have done: added a 6th gear (or "overdrive") to keep the revs down.

 

This is why i am confused why the 115 only does around 43 MPG....which states that my 110 gal does 42 MPGm which is about right in most cases...surely the above figure of 43 is wrong...

[AJ55YOO]

My Mk2 diesel Auto manages 40 to 43 mpg, but I'm told I drive like an undertaker! I do find I really don't need to rev it much past 2500rpm to get the best from it anyway which probably helps...

[mumof4]

Yeehaww!!!!!..I got 48.7 this aft driving in 3rd gear at 40mph.lol.

[Andrew T]

This is why i am confused why the 115 only does around 43 MPG....which states that my 110 gal does 42 MPGm which is about right in most cases...surely the above figure of 43 is wrong...

 

Sanjsanj,

Are you sure you

[william]

With pod on roof and a folding boat, towing a 300lbs sailing boat with piggyback trailer, 3 children and all the trappings of a 2 week walking/sailing holiday in the Lakes, I got 37 mpg over 350 miles in my W reg 1.9TDI Auto with AC on.

 

I'm impressed with this but I never get over 42 with it empy and a steady 70 mph AC off on a 70 mile motorway run to work. (which is why I take the Focus 1.8 TDCI at 55 mpg).

[Guest MATT jr]

just get back from spain, about 3000 miles, and average mpg towing was 27mpg, this is at 60 - 70 mph.

 

towing a 1350Kg caravan,

 

MJR

[mike99]

I am only averaging 37mpg, thats with the car empty most of the time.

 

Its a 115 auto

[Guest MATT jr]

I am only averaging 37mpg, thats with the car empty most of the time.

 

Its a 115 auto

 

is that town? or motorway?

how new is the engine?

 

i get 36mpg round town, which is a mix of econ mode, and a bit of use of "sport mode"

 

its a shame "sport mode" doesnt transform the car into an Aston martin :(

 

MJR

[mike99]

Its a 2001 115bhp with 60k on.

Its the tiptronic 5 speed version so theres no sport mode.

The average mpg is now showing 33, so has dropped a bit but I have only had it 5 days and I reset it when I got it and as I live up a hill I use a bit going up it a few times a day.

My last trip today averaged 15.6 mpg!!

[NikpV]

Its a 2001 115bhp with 60k on.

Its the tiptronic 5 speed version so theres no sport mode.

The average mpg is now showing 33, so has dropped a bit but I have only had it 5 days and I reset it when I got it and as I live up a hill I use a bit going up it a few times a day.

My last trip today averaged 15.6 mpg!!

 

 

If you slam the pedal to the metal the gearbox automatically goes into sports mode (not just the kickdown) it will hold the gear to much higher engine revs than a smooth acceleration

 

has the Maf been changed - if not then its about time - the thick film sensor appears to degrade with age - this will affect both the mpg and acceleration sometimes dramatically (believe me) - new maf is available as an exchange part from fraud for about

[Guest MATT jr]

mmmm, ours is a 2001 115 TDI auto with tiptronic. Sport mode is activated by "flooring it" - its in the manual.

 

but anyway, back to your problem.

 

i would suggest your MAF sensor has gone - or is in the process of failing - this causes loss of power, and increased fuel consumption.

 

simple test is to unplug it, go for a drive, and if its better or the same (performance wise), you need a new MAF -

[mike99]

Like I said I have only had it 5 days so to be honest I wouldn' know if there was a lack of power.

The car I have just sold was a mk 1 zetec tdi 110 and it feels about as quick, maybe quicker than that was so I don't think its the MAF.

I checked the tyre pressures today and They were only mid 20's all round so sorted that.

Don't fancy a new MAF yet as if its not the fault I can't swop it back if its exchange.

[Guest MATT jr]

:wacko: thats very low pressure for a galaxy...

 

just doing the simple MAF test will prove or disprove it - only costs you a small amount of time.

 

if its not the maf - then things might start to get costly.

 

MJR

[mike99]

have not done maf test yet but...

.. I have been out in the car today, first longish journey, did about 90 miles. mpg was 41, thats a mixture of dual carriage way(70) and a bit of in traffic/town driving.

So I now think there probably isn't anything wrong, just the fact that where I live there are hills (n. wales) so I tend to use more.

 

The last Galaxy never had mpg display, if it had of it probably would have said the same.

Now I know why the impreza was so thirsty!!

[mike99]

Just looked at the figures I have for my old car 99 zetec tdi. I kept a record of fuel going in and mileage.

Over 3000 miles I averaged 36 mpg