Hi! I have bought a beautiful British racing green Jaguar xk 4.2 coupe 2007. Now I´m wondering about the preferred fuel. Should I put 98 or 95?

 

95 Ron (US 91 AKI) is the factory spec for your car.

 

Both versions want the good stuff.

 

Another Finn, welcome!

While the car should work perfectly fine on 95E10, I've been told by several mechanics that 98E5 results in slightly cleaner fuel lines etc. Any possible difference is probably marginal, but as the difference in cost is also very small, I decided to go with 98E5.

 

95 RON is just fine. 98 has no additional benefit.

 

Agreed with NO on the E10. Even E5 is too much ethanol.

 

So, in laments terms for this south ga native, I would want to use what we now have as non-ethanol gasoline such as for boats, lawn equipment, etc. or at least 91 octane at the pumps?

 

Don't know if they have that gas in Norway.

Sorry it's Finland.

 

Octane rating has no bearing/connection to ethanol content.

No Jag I'm aware of has ever been harmed by using E10. Beware the sky is falling crowd.

 

My apologies, not intending to hijack this thread. I am asking to learn the differences. It used to be, the higher the octane rating the better, or so I thought. I haven't researched this ethanol thing much except that it seems to wreak havoc on different engine systems, especially those that sit for periods of time. I may be totally wrong on this however.
I appreciate any information shared here.

 

There must be a thousand posts on the subject on this site alone. Please do a search and all your questions will have been answered.

 

Be wary of overly opinionated Canadian trolls, eh?

 

Ethanol gums stuff up. Go ahead and use it all ya want, it makes a mess.

 

I and everyone else in the Northern US and PNW US have been using it for 20+ years, not one documented case on problem case on any modern car. Boats and garden tools are different.

I hope you're looking in the mirror when you say 'troll'.

 

The European specification XK is designed for 95 octane E10 fuel. My 2007 XK did thousands of troublefree miles using it.

I haven't driven in Finland but it's almost impossible to find anything other than E10 in France, Spain or Italy and 98 octane E5 is rare.

Graham

 

Curious. I think I have maybe once seen a fuel station here in Finland that didn't sell 98E5 in addition to 95E10. Teboil actually sells 99E5 instead of 98E5, while Shell at least at some point had a 100 octane fuel.

 

If we had that choice, I'd be using the 98E5 simply for the lower bioethanol content.

Graham

 

From the manual:

 

Even Jaguar knows that ethanol sucks.

 

Unforunately it sucks through the fuel filter, pipes and injectors.

Graham