Guys

Was wondering you could help - I have a skoda fabia 1.4 mpi and its now seriously costing me a fortune to fill up

I have filled up the car to the brim and it returns 240 or so miles (And a full tank is £52) - Does anyone know what MPG that works out as?

I have paid today to get it checked via a diagnostic machine and no errors were reported - The garage also put it on the MOT rank and checked the emissions saying this would identify if it was burning too much fuel. It passed fine apparently

I did ask the garage to check the MAF sensor but they claimed that was not needed as if too much fuel was being burnt then this would be seen when looking at the emissions output

Any ideas please?

Thanks a lot

I get well over 300 miles out of a tank on mine, nearer 400 normally.

Yours doesn't have a MAF so would be a little hard testing that, do you keep it serviced? When we're plugs last changed etc? I'd check throttle body over maybe and carry out a readiness code check, this can be done with diagnostics. It's a systematic test that checks over the fueling system so checks lambda probes, throttle body, EGR (not that yours has it).

52 divided by 1.33 (or whatever you pay per litre) equals 39.097 litres, divide by 4.545 equal 8.602 gallons.

240 miles divided by 8.602 gallons equals 27.899 miles per gallon.

To do this acuratelly you must fill tank to the brim, reset tripmeter, drive until you have to fill up then re-fill to brim again and do the above calculation. If you do this over a few refills adding all fuel used and total mileage covered you will get a more accurate answer.

Edited 6 January, 201214 yr by KeithCheetham

Check tyre pressures. Also think about driving style - particularly gear selection. If you're cruising at 40mph the best gear to be in is fifth, maybe dropping to fourth if needing to accelerate. Anticipation also helps, using the brakes lots uses more petrol than had you kept your foot off the accelerator when coming to a red light etc. Driving at 80mph uses much more fuel than 60mph.

Is 240 miles from brim to the beep/fuel light? If so that's around 40 litres of fuel assuming the fuel sender is working properly. This is about 28mpg.

The Fabia has a MAP sensor rather than a MAF. I tried replacing mine to improve fuel economy, after reading a suggestion of the potential to improve economy, but it was a waste of money. I guess replacing it only helps if there are noticeable running issues/an error code.

On mine the readiness codes seem a bit hit and miss. A couple of them never clear, but if I run the test procedure manually in basic settings and hitting the brake pedal it clears fine.

I get well over 300 miles out of a tank on mine, nearer 400 normally.

Yours doesn't have a MAF so would be a little hard testing that, do you keep it serviced? When we're plugs last changed etc? I'd check throttle body over maybe and carry out a readiness code check, this can be done with diagnostics. It's a systematic test that checks over the fueling system so checks lambda probes, throttle body, EGR (not that yours has it).

Yes but is yours a 1.4 MPI or a different model? I dont believe you can get > 300 miles from a tank on a 1.4 MPI

Check tyre pressures. Also think about driving style - particularly gear selection. If you're cruising at 40mph the best gear to be in is fifth, maybe dropping to fourth if needing to accelerate. Anticipation also helps, using the brakes lots uses more petrol than had you kept your foot off the accelerator when coming to a red light etc. Driving at 80mph uses much more fuel than 60mph.

Is 240 miles from brim to the beep/fuel light? If so that's around 40 litres of fuel assuming the fuel sender is working properly. This is about 28mpg.

The Fabia has a MAP sensor rather than a MAF. I tried replacing mine to improve fuel economy, after reading a suggestion of the potential to improve economy, but it was a waste of money. I guess replacing it only helps if there are noticeable running issues/an error code.

On mine the readiness codes seem a bit hit and miss. A couple of them never clear, but if I run the test procedure manually in basic settings and hitting the brake pedal it clears fine.

I drive slowly and always use a high gear - I also am good in anticipating stops and always try to keep moving and not touch the breaks

I have checked the type pressures and they are 30 all round

How many miles do you get from a tank?

Yes its 240 from brim to fuel light - Did you manage to improve fuel economy by changing anything? I have a 11 year old fabia with low mileage so I wonder if anything needs changing

Yes but is yours a 1.4 MPI or a different model? I dont believe you can get > 300 miles from a tank on a 1.4 MPI

Yep 1.4 MPI

Often doing motorway runs down to MK from Worcester, 200 mile round trip and use half a tank.

Yep 1.4 MPI

Often doing motorway runs down to MK from Worcester, 200 mile round trip and use half a tank.

Is it the 8v or the 16V?

What year is yours?

8v, 2001 on a Y plate.

I have checked the type pressures and they are 30 all round

I keep mine at 33 psi all round. The recommended pressures are in the fuel filler flap, but if you're used to PSI, are unhelpfully quoted in bars. http://www.centauro-owners.com/articles/psibar.html should help.

8v, 2001 on a Y plate.

So how can this be possible then? How can I get 240 miles from a tank and you get 400?

The car has 45K miles and I replaced the plugs a while ago as I wanted to improve fuel performance.

I drive it very carefully and always use a high gear where possible.

I drive like Miss Daisy and my 1.4 16v only returns around 21 / 24 MPG around town.

Not too bothered as I have only done 700 miles in the last year

Changing the thermostat on mine helped at first.....temp needle used to take upto 5 miles to hit perpendicular, now in under a mile. If the engine thinks it's running too cold, it sends a richer fuel mixture.....that's what I understood from it. Cleaning the throttle body and MAP sensor also helped. Brought up motorway mpgs from about 30 to 35.

Unfortunately I'm back to crappy mpgs similar to what you're getting (26-28)......mixture of increased town driving and lambda problems.

I could probably achieve better with a more conscientious driving style....but I am sad and pretend my MPI is a VRS.

Edited 28 February, 201214 yr by fsa

I read this thread before getting my 1.4mpi and i've got to be honest it nearly put me off buying it. However i'm pleased to be able to say my car is consistently returning 40mpg with 400mile tank ranges before reserve (I used the ventectomy trick on one tank). I tend to do a lot of longer journeys but even doing shorter runs and going to visit family etc 4 up with a full boot i've not managed to average under 40mpg on the last 1,250 miles, i'm now experimenting with dropping the speed slightly (65 vs 70mph) as i'd love to know what you have to do to get the claimed 50mpg extra urban.

^^ :o

Jealous!

In fairness despite being Y reg it's only got 23k on the clock with FSH based on time so it's barely run in. It's not all cheap motoring, the dealer network has had over £160 of my hard earned this month in parts (angle sensor, 4 nipples - ooer! - under seat storage box and a cup holder).

In fairness despite being Y reg it's only got 23k on the clock with FSH based on time so it's barely run in. It's not all cheap motoring, the dealer network has had over £160 of my hard earned this month in parts (angle sensor, 4 nipples - ooer! - under seat storage box and a cup holder).

Mine is as old as yours, 51 reg, but 70k. Angle sensor went already?? Guess that's the next thing I should expect in mine....oh the joy!

Ok. Checklist:

• Tyre pressures - reduced economy due to more friction if pressure isn't right.
  
• Thermostat/temp sender - overfuelling occurs if the engine thinks it's cold. Thermostat housing has been known to crumble.
  
• Throttle body - gets gunked up due to rocker cover recycling oil/exhaust gases back to the throttle body. My fix was to vent it to a catch can.
  
• Spark plugs - make a fair bit of difference if not working properly.
  
• Aircon - obviously running an mpi with aircon severely hampers performance and fuel economy (as if it wasn't bad enough!).
  
• Oil - making sure the right oil in the car and is changed regularly makes a fair bit of difference
  
• Pre-cat lambda - if the temp sender is on the fritz then it will overfuel - resulting in potential carbon deposits on the pre-cat lambda via unburnt fuel. If this happens, over time it'll goose the pre-cat lambda resulting in more overfuelling. Bit of a vicious circle.
  
• timing chain - if your timing chain is rattling... It can affect fuelling. Good for 120k miles according to Skoda but if driven hard the chain can be gone before 50k.
  

I'm sure there are many more that i'm not listing, but i'm tired. Meh.

Hope this helps