I have had my Skoda fabia 1 .4 TDI for 12 months now . Had a new mot and service done recently but I've noticed I'm only getting max 48 mpg around town . When I bought it I was getting easily 55 mpg . Any ideas anyone ? 

Welcome.

Was that 55 mpg worked out on actual fuel bought & brimming the tank and brimming again or what showed on the dash?

 

Is the dash reset and the tank filled again because at the service and MOT the car sat with the engine running for a while and going no place. 

 

?

What did the service involve, was it just Oil / Filter & Air Filter or was the fuel filter changed, anything else?

Have you checked the tyre pressures since the service, or have you had new tyres fitted?

Edited 13 January, 20224 yr by roottoot

I had both Tony tyres replaced . Oil filter fuel filter and air filter all replaced . All readings off the dash.  I've reset them to zero . Just seems strange how it's dropped by that much.  

If it was the front tyres then i doubt your new tyres circumference is identical to the ones replaced if they were worn.

Not sure your fuel use has dropped by that much if the figures are from the dash and not from actual miles driven and litres of fuel used. 

Edited 13 January, 20224 yr by roottoot

2 minutes ago, Fabialee said:

I had both Tony tyres replaced . Oil filter fuel filter and air filter all replaced . All readings off the dash.  I've reset them to zero . Just seems strange how it's dropped by that much.  

 

That readout is not accurate and can be safely ignored.

It's my first diesel car , do I'm over the moon with my mpg anyway . I realise the dash read out is not always accurate. Thank you for your reply 

13 minutes ago, Fabialee said:

I had both Tony tyres replaced . Oil filter fuel filter and air filter all replaced . All readings off the dash.  I've reset them to zero . Just seems strange how it's dropped by that much.  

 

I suppose that new tyres with full-depth & new tread and maybe a differing ‘economy factor’ could make some difference for a while and it could start to creep up again as the tread wears. Doesn’t sound like a huge difference though 

 

11 minutes ago, sepulchrave said:

 

That readout is not accurate and can be safely ignored.

 

Also agree that the trip computer isn’t a perfect system, but it is what most of us tend to refer to 🤨

13 minutes ago, Pilotguy said:

Also agree that the trip computer isn’t a perfect system, but it is what most of us tend to refer to 🤨

 

It's hopeless, the ECU really has no idea how much fuel is in the tank, it uses an algorithm to approximate how much fuel is being injected, but since the mileage measurement isn't accurate either it really can't be trusted.

 Has the drop in economy been long term or over a short time. What time of year were you "getting" 55mpg, as summer vs winter can have an effect especially if short journeys - reportedly summer and winter grade diesel fuel but unsure if these will give different economy - and is your drive route generally the same. My 1.4 TDI Greenline shows a slight difference in economy through the year which is checked with the brimming/zero trip method, I have always had an issue with water temp readings as viewed through Torque never really being stable or reaching 90 deg,C which a new thermostat has cured so will review over time if this effects economy - 90C reached regularly now even over short journeys as I live on the edge of the Pennines so regular hill climbs.

 While this will not assist in comparing with previous reported economy via dash, to measure more accurately fill tank to brim, zero trip, use most of fuel in tank, re-fill noting litres to brim again, note distance on trip and re-set. Miles travelled divided by litres added multiply by 4.545 to give mpg. Obviously a few tanks will allow trending. On mine last trip reading 297 miles divided by 28.3 litres fill times 4.545 equals 47.7 mpg.

Wow, you make it all sound so interesting.

 

I bet you drive an extra 10 miles to save a quid on a tankfull.

 

My 2.0 may be thirsty but it more than makes up for it by literally costing f**kall in repairs over the last five years, it's just SO reliable.

@KeithCheethamjust a small point, well three back from the small point.  As I always have to remind my wife, as she can never remember, one of the few numbers I can remember is the number of litres to a (UK) gallon, it's 4.546 (as its a '0' after the 6 it's not a round up either).

 

Even though going to three decimal places when working out pump fill to trip I do it out of habit because my wife asks rather than just going with 4.5.

 

Also something of great interest to the likes sepulchrave no doubt(?), my wife always mixes up Deep Purple with Black Sabbath when she hears either of their hit singles on the radio (wireless).

 

Edited 14 January, 20224 yr by nta16

 No Sep, I always go and buy that inferior quality - in the opinion of some people who do not know what a British Standard and quality control are - cheap diesel from Tesco to get the clubcard points for cost reduction on roadside recovery, which I have needed once in the last 15 years when a gearbox bearing on my 1st 1.4TDI collapsed rendering the car immobile at a far from ideal position on the road over the Pennines.

The main reason for the lengthy reply was the usual posting of "my car has an issue" full stop, with no history or facts to allow a purposeful reply. This is not a harsh reply to the OP but I quick outline of what is required for support.

46 minutes ago, nta16 said:

...of great interest to the likes sepulchrave no doubt(?), my wife always mixes up Deep Purple with Black Sabbath when she hears either of their hit singles on the radio (wireless).

 

 

Tell her it's ok to mix spirits but to stay away from the whine.