Few months ago I have bought a Skoda Fabia 1.2 HTP and since the beginning it had some issues. We changed the catalytic converter to a new one but not original Skoda part which is now causing check engine light to show up from time to time. My current fuel consumption is around 270 miles per a full tank. I am doing average of 75 - 85 mi/h on a motorway commuting to work and back, doing weekly around 250 miles. My Skoda has 133000 on the clock currently. My mechanic claims they simply have such a mileage which I decline to accept reading some of you here are able to do 500 miles on one tank. Can you suggest anything or a good Skoda Specialist in Bristol or Weston super Mare area.

How many litres is used to get 270 miles as 'Full tank' really gives no idea of the MPG or miles per litre you get.

Maybe try 70 mph max speed on the motorway and see what MPG you get.

 

An Average 75-85 mi/h must mean sometimes hitting 90-100 mph.

I do agree in means hitting 100 but this happens very rarely. At the moment I am not going faster than 85 mi/h due to high fuel consumption. I filled my tank on 21/1/2020 with 38 litres of fuel. I do not expect to do more than 250 miles on that this week.

Anyone with a mk1 Fabia doing 500 miles to a tank has a diesel engine.  

 

You have the wrong engine for doing those sorts of speeds and hoping to get good economy.

 

Ours (1.2, 12valve), driven on mixed roads but fairly gently by my partner, manages only about 42 mpg long term average. 

 

Scan the car to find out what the fault light is trying to tell you, fix that and things may improve slightly.

Edited 21 January, 20206 yr by Wino

It's a small engine and you're thrashing it too hard, however it's possible the thermostat is stuck or the coolant temperature sensor needs replacing. Is it using any oil?

I am getting Code P0171 - System Too Lean which I attribute to catalytic converter not being original from Skoda. It is kind of a sad thing that this particular one does have a better mileage. 

Check the hard plastic vacuum hose going to the brake servo. When they crack and leak at the joints, this code can appear.

1 hour ago, Palito said:

I am getting Code P0171 - System Too Lean which I attribute to catalytic converter not being original from Skoda. It is kind of a sad thing that this particular one does have a better mileage. 

Get a voltage reading from the lambda sensor; if that goes wrong it can cause a too lean or rich mixture.

Lambda sensor was replaced together with the cat. so I assume it is working in order but will do some checks and report back. Thank you very much for all the hints.

38 minutes ago, Palito said:

Lambda sensor was replaced together with the cat. so I assume it is working in order but will do some checks and report back. Thank you very much for all the hints.

 

There are two lambda sensors, pre cat and post cat, I assume it was the post cat sensor that was replaced?

Yes it was. Isn't the other one attached to the cat itself?

49 minutes ago, Palito said:

Yes it was. Isn't the other one attached to the cat itself?

 

No, it's upstream of the cat, it's the sensor responsible for mixture control, if you're burning that much fuel but the ECU reports the mixture as lean then as Ken rightly suggests you need to test it but tbh it's probably quicker and easier to just go ahead and replace it.