About a year and a half ago I got a steal on a salvaged 04 350z with 25k on it, I drove it as is for a year until we had the money the fix most of the body damages. In that time it got about 30 mpg, but then in june we took it in to a local shop for the repairs. it was in the shop for three weeks getting the body fixed, paint redone, etc. After i got it back the mpg had dropped to 23.1 and hasn't gotten better than that since, any ideas in what caused that?

 

MPG is a poor diagnostic tool.

 

Are you doing it by the mpg on the dash or are you doing it when you fill up?
I never rely on the dash mpg. True MPG need to be done when you fill up divide the total mileage by the gallons on fill up contine to do for 3-4 fill up that will be the most accurate.

23.1 is pretty good that about what I get btw. I am some what heavy footed

 

I used to get 23mpg until one day i reset the gauge and have been getting 19-20mpg ever since. Idk i didn't notice a huge drop on refills between trips. So i just leave it alone.

 

Always happy to help. If you have other questions please do not hesitate to waste my time.