So I take in my 07 460L for the 80k service (currently have 78k) and the dealer tells me I need all four control arms etc replaced. Great because I still have the platinum warranty so I ended up paying for the service. The service included a fuel system cleaning which I though was great until I got the car home. After driving for about a week I noticed I was filling up more frequently so I reset everything after filling and and noticed I was getting around 12 mpg🤦*♂️ Anyone ever have this problem?

 

Wow 12 MPG. I just don't see how a fuel cleaner could cause such a drop. What were you averaging prior to this.

 

Take it back immediately. If your gas mileage is this low, you have a fuel leak!

 

I'm curious, how much did they charge you for this "fuel system cleaning"?

If I had to guess I would say that this was an unnecessary high profit add on. If you are using any brand name premium gasoline, or using an additive such as Techron, there is no need for "fuel system cleaning".

I would definitely take the car back, something is seriously wrong.

 

Honestly man Ive been averaging like 14-15 mpg's since I bought my car

I do spend a lot of time in real city traffic, but with a mix of highway I think I should be higher

12 does seem very low , and I don't know what is involved in a "fuel system cleaning" sounds like a scam to me

Id ask them exactly what was done, maybe bring it back like others have said

 

Ah, 14-15 mpg is pretty bad. You're going to need more miles to accurately say you're now only getting 12mpg and that this is significantly lower than you were getting before. I get 20 around town and 30 on the freeway (at 80-85).

Agree, you probably didn't need the "fuel cleaner".

 

This is an odd one. Did you possibly go to a different gas station than usual? More than once perhaps? I am just wondering if perhaps regular unleaded was used instead (some gas stations are shady and sometimes the wrong grade is accidentally misplaced) and or was simply a bad batch of gasoline. For instance, if it had higher than 10% of that evil ethanol. Also, are there places in Cali that sell 100% gasoline? With CARB being pretty hard core, it would not shock me if it was not readily available. The app Pure Gas is awesome for finding gas stations in your area that sell it and is available for free on iOS and Android.

While something like a fuel leak is certainly a possibility, I would think you would be able to smell it. Moreover, given the myriad sensors, you would think if something really wrong was afoot, the dash would be lit up like a Christmas tree...

 

My 2015 LS460 F-Sport got about ~16mpg in mixed highway/local driving, and about 22mpg on a stretch of 300 miles of highway driving. All are with premium fuel.

The numbers are not far from EPA ratings, but seem much lower than most ppl quoted. Thoughts?

 

AWD? Looking at where your location states and the year, would be shocked if otherwise. If so, it certainly affects the mileage. If driving somewhat "spirited" I have gone to around 17.8 or so when driving locally. I do take the interstate whenever possible.

 

I hit reset on all my averages and I'm getting much better numbers now

about 17-18 average, and I achieved 26mpg on a 3-4 hour highway trip yesterday , so I'm happy now

 

I used to get around 14mpg around town, but I've been known to have a slightly heavy foot.

 

Winter fuel combined with the temp / short trips = the worst mpg all year.

 

This. In the winter it's normal for your consumption to drop 2 - 5 MPG.

 

Ugh. Thank God we don't have to deal with "winter fuel" in these parts. Only diesel gets a treatment for cold weather.

 

24-28

got it scheduled for Feb 8. Will keep you guys posted