Hellequin said:what is the reason for running a 2.5 engine on the more expensive higher grade fuel and does it really make a difference?
Lazza said:... That way I didn’t have to worry about trying to find high octane fuel when in the wilds of Scotland/Wales/Berkshire ...

Busterboo said:Lazza said:... That way I didn’t have to worry about trying to find high octane fuel when in the wilds of Scotland/Wales/Berkshire ...
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Paulr said:My engine warning light usually comes on after a few hundred miles when I use supermarket lower grade fuel. Never does when I use super unleaded.
Gaffa22 said:Paulr said:My engine warning light usually comes on after a few hundred miles when I use supermarket lower grade fuel. Never does when I use super unleaded.
That's because low grade supermarket fuel contains 5% biethanol, some cars don't like it, it messes with the lambda sensor
I’m sure it would be fine with main brand standard fuels.Paulr said:Gaffa22 said:Paulr said:My engine warning light usually comes on after a few hundred miles when I use supermarket lower grade fuel. Never does when I use super unleaded.
That's because low grade supermarket fuel contains 5% biethanol, some cars don't like it, it messes with the lambda sensor
Which is exactly the code that comes up! Fill it up with better fuel, clear the code and it is fine!
buzyg said:Berkshire.. Oh the risk some people will take with their Zeds.
Paulr said:My engine warning light usually comes on after a few hundred miles when I use supermarket lower grade fuel. Never does when I use super unleaded.
Fixed that for you.IRD said:Check the Telegraph website and see what Honest John writes. Then do the opposite.
Lazza said:I’m sure it would be fine with main brand standard fuels.Paulr said:Gaffa22 said:That's because low grade supermarket fuel contains 5% biethanol, some cars don't like it, it messes with the lambda sensor
Which is exactly the code that comes up! Fill it up with better fuel, clear the code and it is fine!
My diesel Merc never liked Sainsbury/Asda diesel. They made it sound like a bag of spanner’s. Tesco and all the main brands were fine.