Yesterday I ran out of gas, going to a friend's house, and my wife "rescued" me with 5 gallons of 87 octane lawnmower gas.(I didn't know) I filled the rest up with the best 91 octane I could find around me. Now I am getting a restricted performance message on my dash. Could the octane cause the message, and do I need to put some octane booster in the tank.....Thanks.......Mike

 

I know of at least one member using 87 octane in his XK8. Several use 89, and it just results in a slight loss of power. The ECU will retard the timing if the knock sensors detect preignition.

 

Mike,

I think the front undertray needs lowering.



You're not getting an even cut there with your new lawnmower.

With running out of fuel there's always a risk of cat damage so it's worth checking for error codes.

As you've topped the tank with 91, the 5 gallons of 87 is already diluted nearly 3 to one. Run it low and fill again with 91 and you'll have got rid of it.

Graham