High consumption, normal performance

hello

"I've noticed an increased fuel consumption during the last two fill-ups, but I've been driving roughly the same distances and at the same speeds. The car is driving normally otherwise. The only thing that's different is that I have new tires, but they have the same rolling circumference and width, so it probably isn't the cause. Could there be a defective or dirty component in the 1.Z engine that could explain the increased fuel consumption?"

Best regards, Christian.

Hello,

'Just because the tire sizes are the same doesn't mean they can't cause increased fuel consumption. Just read a tire test; you'll usually find a section on 'rolling resistance'.' It can vary significantly even when the dimensions are the same.

2) Of course, anything can be broken in the entire system (Z), which can lead to increased fuel consumption while maintaining almost the same performance.

Conclusion: If the problem started precisely when the tires were changed, I would suspect the tires. If it continues to rise: Engine troubleshooting.

Regards,
Private.

Hello,

'More is relative - how much more?'
2 liters? Are those still the tires?
0.2 liters? Wouldn't that fall within the measurement tolerance?

Even though I still refuse to believe it, I need at least 0.5 liters more fuel with the winter tires, no matter how I calculate or measure it. That's almost 10% more than my normal fuel consumption. It could very well be due to the tires.

Generally speaking, I would say that new tires need more air pressure than old ones, because the older tires are already harder, and also because they have less tread to work with, which means less flexing.
I would currently consider this to be the main cause if the volume is within the range of 0.5 liters.
Opinions on this?

Well, I can only agree with Garth on that. Depending on the rubber compound used, there can be differences in fuel consumption of a few tenths of a liter, even with the same dimensions.

However, I would definitely also check the air filter and the intake manifold located in front of it. It's a quick check. If a larger clump of "dirt" has accumulated in that area, your turbocharger will have to work much harder to provide the engine with the necessary amount of intake air. The consumption can increase quite significantly.

Regards,
Alex.

hello

I meant approximately 100 km less per tank, so about 0.6 liters more. And I've already checked the intake manifold, but everything seems to be in order.

bye christian