2008 Civic Sport Change in Fuel Economy

[Lifers]

Heya Folk,

2008 Civic Sport (2L - 45k on ODO), gets driven a little hard, filled with E10 usually gets 500km per tank.

Last few months the cheap day keeps changing, so I seem to have lost sight of how many kms I get, but in the last few weeks definitely I'm only seeing 400km/tank. A 100km difference seems to be quite drastic (although it might have crept up over time).

I've tried driving a bit easier and stopped using flappy paddles, I've switched to 95 for a tank, I've increased inflation in the tyres by a few PSI, Oil level is a little below average (there may be a small leak) and we're half way to the next service, it's not black yet. Haven't checked the air filter but don't recall driving through the desert!

Tyres were changed, but from Bridgestone to Bridgestone, it's not like they're sticky rubber. Similar level of city driving and traffic (although I haven't burnt an entire tank in a road trip for a while).

Otherwise car appears to be normal, same level of power, same idle level, no smoke that I've noticed, very little use of A/C.

Any ideas why I'd have such a drastic change in fuel economy?

TIA

[xenonkuraz]

Check your maf sensor isn't covered in dirt. If it is buy a can of electronic solvent cleaner and spray it on

[Lifers]

OK I might have written this a little early.

On the current tank I had done 400kms and there were only three 'dots' left on the petrol gauge. I thought there was no way I was going to get 100kms out of three dots, because the last few dots seem to disappear the fastest.

However I just got 30kms out of the 3rd last dot going to dinner, so if I get 60 out of the last two it gets me to 480km with no dots, and then I know I can get to about 500km.

Perhaps I've been driving harder than I thought... But it looks like this tank of 95 is going to get me to 500.

[xenonkuraz]

When the fuel light appears you have about 7 litres left. You should still be able to get 450km before your light even goes on in any driving conditions. If I can get 600km the way I drive anything less is possible. Check if your o2 sensor has gone