Hello All,

I'm looking for some help with the fuel consumption on my 54 Fabia VRS. I was getting around 53mpg up until last week. Now my fuel consumption seems to have worsened to nearer 43mpg! On one day I changed 2 things on the car which could affect this:

• I replaced all 4 worn out Michelins with Kumho KU31s
  
• I replaced all 4 worn out brake discs and pads with Febi Bilstein discs and pads
  

I've slackened the handbrake off a bit in case that was binding, but I can't think what else to do.

If anyone has any advice/experience with big changes in mpg due to tyre changes, or can advise how I can check for brake drag I'd really appreciate it. At this rate the money I saved on the tyres will be spent on diesel in only a few thousand miles.

One last point, in case relevant. A couple of weeks ago I performed the 'cage mod' on my MAF sensor connector.

Cheers,

Neil

have you checked to see if you brake pads are binding on your discs could have the wrong discs and or pads

not the hot weather is it?

Thanks for the help so far.

In desperation I have just been out and checked each wheel for free rotation. The rear wheels spin freely for several turns before stopping. The front wheels are a little stiffer, I assume because I am turning over parts of the xmsn. None of them felt like they were binding. I've checked the tyre pressures again as well with a proper pencil gauge.

I probably got my worst mpg run today at the lowest ambient temperature so I'm pretty sure that's not a major factor.

Has anyone had a big swing in mpg going from Michelins to Kumhos?

Cheers.

Michelins are the most economical tyres available. Absolutely, definitely, but 10mpg? That's a huge difference. I can't help but think that a brake is catching somewhere.

Hot weather. I've done extensive MPG test on the VRS and the best MPG is between 12 to 18 degrees c. Last week when the temperature hit 25c my MPG dropped to mid 40's from mid 50's.

Take it for a run in the evening when it's cooler. I think you will find there is nothing wrong with it. If you've been running aircon, that will drop the MPG as well.

I averaged 40mpg over 9 months and 15,000 miles in mine.

Strangely enough my consumption has dramatically increased since fitting 4 new Falkens.

Was averaging 50-52, now down to 45-47.

Hi,

When I recently changed my vRS tyres to Uniroyals from Bridgestones I also noticed a drop in mpg from 54 to to mpg.

Now the tyres have run in mpg has improved to 52 mpg.

Maybe it is a combination of new tyres with hot weather with aircon use

Hi,

previous post is drop to 50 mpg

I'd go with the heat too... my fiat normally gets to about 57 mpg on the work journey, on these hot days, it's felt crappy and returned about 44 mpg....... now it cooled again, its back to its usual self

Ambient temps have been reasonable for a while now.....

I would be looking at the air filter.....

My fuel consumption dropped when I fitted Goodyear F1s to replace the OEM Bridgestones from around 50mpg to 45mpg. I'm not doing a lot of mileage these days so I'd rather have the grip.

All - thanks for your help/comments on this. Things seem to have settled down a bit and I'm now seeing more like 48-49mpg which is still lower but probably explanable just due to the tyre change. I suppose over the life of the tyres the saving over Michelins will be about offset by the worse fuel consumption. For what it's worth I'd have bought Michelins if I had my time again - the Kumhos are a little quieter but I don't think the handling is any better and the Michelins had a rubber ridge on the side walls which gave a little bit of curb protection!