A quick detail not to overlook.
2010+ V6 recommends premium due to increased compression.
2007-2009 has a lower compression and so regular is recommended.

 

What will happen if i do 70% regular and 30% mixture , thats for the 2012 V6?

 

I have the 2010 with the higher compression engine as does vad and we both say it's fine on regular..

The compression increase added like 3 hp and made it an interference engine...worst case is it knocks and the ecu changes the spark timing so you get less power...I noticed noting running regular for the last few tanks.

 

Wrong. Worst case is it knocks, vaporizes aluminum (a result of knock) off the top of your pistons and deposits them on your spark plugs and valves.

Backing off timing is what happens afterwards.

 

You aren't doing it any favours by using 87 octane. If premium is recommended, there is a reason for it. Using 87 can lead to driveability issues, such as performance and things you cannot see, feel, hear or smell because your computer is doing everything to correct it.

87 is fine if you can't get premium. I know a guy with a BMW 5 series where it says 87 is acceptable....thats what he did and he kept paying for fuel system and sensor repairs. Started using premium and not only did it feel powerful it also got better mpg. If you can't afford the 15 cents extra a liter, buy a Hyundai.

Overall it is your vehicle, the warnings are there.

 

Hi all,

This is my first post here. I am purchasing a 07 XLS. I believe that it recommends Regular. Would I gain or hurt anything by using mid-grade (89) fuel in it?

Thank you,

Rafster

 

you won't hurt anything, but as stated earlier. 89 octane fuel is harder to ignite than 87...so your fuel efficiency will decrease. How much? who knows...but remember regular/mid-grade/premium has nothing to do with the quality of the fuel and everything to do with the ease of ignition of the fuel.

 

Thank you for the answer!