Hi All

I have a 56 plate Octavia 1.9TDI PD Ambiente Estate with 166000 miles on the clock. Service history is good from previous owners.

My concern is that according to the multifunction display shows average mpg (assuming it is mpg rather than litres/100km) is less than 20!!!!!

Any ideas what the problem could be or where I could start trouble shooting?

I have only had the car 10 days or so and I am worried I have bought a dud.

Many Thanks

Liam

Is the thermostat ok? ( does it warm up relatively quick, tyre pressures ok? have you given it some welly on the motorway to clean the injectors, have you reset the gauge and then done a steady run

Gets up to temp ok (90^oC), tyre pressures seem ok. I haven't had a chance to give it a long blast but have tried to give it some welly. I did the reset as detailed on http://www.briskoda.net/forums/topic/146724-re-map-not-feeling-like-it-used-to-read-on/ (the foot on throttle, ignition on to dash lights on, wait 10secs etc, not the battery disconnect one) then reset avg MPG (trip 1 not trip 2) and took it for a 15min drive of all sorts of speeds and got avg of 18.6mpg

The only accurate method is to fill up each time and note the mileage. The fuelly app and Web Page is a convenient way of going it.

Sent from my GT-I9100 using Tapatalk 2

I would very much doubt that the car is giving those kind of MPG,s not even an abused VRS would return that figure. How is the performance of the engine? Sluggish and smoking?

Also might be worth having it scanned for fault codes first.

At its worst lowest mpg mine was 45 but it's always 59 plus usually.

Good luck hope you sort it out

Either the brakes are stuck on, you have a fuel leak, there are clouds of black smoke coming out of the exhaust or the MFD is wrong.

This always makes me chuckle in the many MPG related threads.

"My car is doing xx MPG", no your car is telling you that it is doing xx MPG!

As above the first thing you need to do is a manual check by filling the tank, resetting the trip meter and then running it to the red, refilling and making a manual calculation using the actual mileage and litres of fuel used. This is your real MPG.

The OBC (onboard computer) can be (and often is) quite accurate as the car knows exactly how fast you are travelling and how much fuel it is injecting into the engine, however computers use sensors and sensors can fail or become inaccurate.

Manually calcultaing your MPG will allow you to determine whether the OBC is at fault or whether there is a genuine issue with the car.

When I read the thread title I was expecting it to be about exceptionally high MPG

When I read the thread title I was expecting it to be about exceptionally high MPG

Haha. I'm not the only one then?!

I would very much doubt that the car is giving those kind of MPG,s not even an abused VRS would return that figure. How is the performance of the engine? Sluggish and smoking?

Also might be worth having it scanned for fault codes first.

At its worst lowest mpg mine was 45 but it's always 59 plus usually.

Good luck hope you sort it out

I got 18mpg on the 'Ring the other week

LOL but not diesel though?

LOL but not diesel though?

Yes 170CR!

18mpg!! That was abused then but I bet it was fun

i had crap mpg from my pd fabia,the maf was knackered

i had crap mpg from my pd fabia,the maf was knackered

This is fairly easy to diagnose.

Just floor it in third and if it starts feeling wheezy/the power drops off after 3000rpm then it's probably broken.

Phil