Issues Since Tyre Change

[JayISSE]

Hi,

This is my first post so forgive me if it's in the wrong section.

I have a Lexus IS200SE, and it's been fine for the 1 and a half years I have had it, it's pretty low on mileage and had only done 35,000 miles when I bought it.

I recently had my 4 tyres changed as they were worn so replaced them with the same ones (new) (Bridgestone Potenza's).

Since then, my petrol consumption has increased dramatically!, I understand that to a certain extent it will change somewhat having 4 brand new tyres, but not nearly as much as it has. Almost double.

Acceleration has also been affected slightly but this isn't my main issue, it the amount of money I am now spending on petrol.

Has anybody got any ideas as to what this could be, is this normal during the first few weeks of having 4 new tyres (more traction/drag etc) or should it be the opposite.

I ensured that they were inflated correctly but haven't had my tracking done.

If anyone can suggest anything then it will be much appreciated.

also completely unrelated to the above although it's happened at the same time, when my lights are on auto and my fog lights are on too, it used to only shut the headlights off when the ignition was switched off, leaving the fog lights on and beeping when I opened the door, now it switches all the fog lights off al well when the engine is turned off? Not sure what's changed.

Thanks

Jay

[darkoracle]

Jay, I'm no expert but I just don't see how new tyres could have that effect.

How are you monitoring the mpg/mpl - onboard computer or your own manual method?

An outside possibility is that brakes have been disturbed when the wheels were fitted and could be binding.

Have you noticed any pulling to one side when brakes are applied?

Are the tyres rotation specific - if so have they been fitted correctly?

Were they balanced properly?

That's about my limit.

If it gets no better in the next few miles, I'd contact the fitters and see if they have experienced this before and ask them to check it over.

[ChrisIS200SportTTE]

Hi, I'm of the same opinion as above. I don't see how 4 new tyres can decrease your MPG so significantly!

Even if they are un balanced the mpg difference should be so small that you won't notice it!

[clifton 94]

Hi when your headlights and fog lights are on and the switch is set to auto they will switch off when you remove the key and open the drivers door. The first thing to check with your tyres is the pressures should be 34 psi putting new tyres on will not increase your fuel consumption at all because new tyres do not have as much grip as tyres with a few miles on .Have you any warning lights come up on the dash