I keep track of my MPG's in a google spreadsheet. I average 18 - 21 and do a mixture of highway/local street driving in Chicago.

 

Hmm something is definitely off according to fuelly app and my car average mpg im getting around 12.4 mpg on fuelly and 12.2 on car reading. This is Me fuelling up 2 times already from about 20 cruising miles to fillup, using same gas station eacch time. Ive reset the car by disconnecting the battery for 30min all tires are around 32psi. Im stumped any suggestions?

ninja edit: i think ill try the fuel injector service to see if it makes any difference. My Ls a awd

 

How many miles, about, did you travel before refueling?

Also, everyone, don't forget..."winter" gasoline, so extra added air. There's actually less fuel in winter gasoline than summer because they're still trying to prevent the lone 1978 Thunderbird used for commuting and with a stuck choke from polluting a maximum amount.

I've personally had winter gasoline put a 20%+ hurting on MPG numbers in an '82 Lincoln Continental.

Nothing like going from about 16 to sub-teens!

 

Here's a thread that might be interesting to some of you if you are using your car's MPG calculations.

https://www.clublexus.com/forums/ls-...is-so-off.html

 

I don't think "winter gasoline" (containing MTBE) is used any more - it's 10% ethanol year round. However, colder temperatures in winter could cause a slightly lower gas mileage. I agree, though, low teens is not normal.