Hard to find premium gas after hurricane Sandy here on LI. Will probably have to keep using regular for a few more tank fulls until supplies of premium come back. I had to fill up with regular tonight. Has anyone run their XF on regular. Anything happen? Does anyone regularly run on regular or mid grade gas. Is the difference noticeable?

Thanks

 

You will be OK as long as you don't push her too hard. You will notice more hesitation and a feeling of "laying over" has the rev go up.

 

Its all computer controlled these days. You won't hurt the engine, but you won't get the advertised HP and torque.

 

Here is the XF Fuel requirement advice from the UK Driver's Handbook. I've outlined the section on lower octane in red:



Lower grade fuel gives reduced performance but short term use of lower grade fuel should not cause any damage.

The Note gives a warning about engine 'knocking' which can cause damage.

Graham

 

Try out Hess gas stations, they usually have Premium.

I have been on the same boat as you, but refuse to use regular. The sensors are supposed to make adjustments, but they don't always exactly get rid of the knocking.

if you can't find Premium, use a bottle of octane booster for the time being.

 

Note that the recommendations given by Jaguar and posted by GGG mention octane ratings using the 'RON' designation (research octane number). Gasoline sold in North America uses the AKI (anti knock index) rating system which is quite different and confuses many owners.

A rough conversion :

95 RON = 91 AKI

91 RON = 87 AKI

so operating your car on 87 is acceptable with a caution that max performance may be reduced. Many of us 'S typers' run our cars on 87 with no noticeable affects at all.

Hope life on LI gets back to normal soon.

 

you'll be fine, the engine will control the firing. filling up regular a few times wont cause a problem.

 

AKI is not quite different, sometimes referred to as Pump Octane marked on our pumps this is just the arithmetic average of the two AKI accepted standards resulting from actual knock testing against the reference 100 Octane fuel Motor Octane Number (MON) and Research Octane Number (RON). The pump octane number isn't really a number at all.

Your conversions at correct. For practical purposes RON is four points higher than Pump and MON is four points lower in the range of current motor fuels.