bobby0600
06-20-2016, 10:49 AM
Hi all, I am having a mysterious issue with the mpg on my car. I currently live in Oklahoma, but am originally from Indiana. I have a 2009 Yaris Hatchback with 165K on it.
A week ago I drove north to Indiana for a visit. While there, my home mechanic (Toyota Certified) installed the new fuel sending unit and adjusted the serpentine belt so it would not squeal (it's a new belt with less than 2K on it). On the way to Indiana, the car averaged 39mpg, but on the way back to OK it decreased to 37.13mpg, 36.02mpg, 36.34mpg and finally 36mpg. I used the exact same gas stations both ways (MotoMart & Phillips 66) and 89octane fuel. I figured the first reading was due to some city driving before leaving town, but was not pleased when it kept going down. The engine also shifted into high gear to maintain cruise control more often than on the original trip.
Could this be due to the belt being too tight? My mechanic said it was 'really tight' and was concerned about it wearing things out, so he did loosen it a bit before I drove away. Or did not having access to ethanol free fuel like I do in OK affect the performance that much? My driving was less aggressive on the return trip, so I doubt that was the issue.
I being paranoid? I've had the car for just over a month and loved it so far. I installed cruise control thanks to CTScott's great tutorial and replaced the fuel sending unit because it annoyed me that something so major wasn't accurate but I'd prefer not to have anything vital to operation break on the car yet!
Thanks in advance for any ideas! (Including telling me I'm worrying too much!)
A week ago I drove north to Indiana for a visit. While there, my home mechanic (Toyota Certified) installed the new fuel sending unit and adjusted the serpentine belt so it would not squeal (it's a new belt with less than 2K on it). On the way to Indiana, the car averaged 39mpg, but on the way back to OK it decreased to 37.13mpg, 36.02mpg, 36.34mpg and finally 36mpg. I used the exact same gas stations both ways (MotoMart & Phillips 66) and 89octane fuel. I figured the first reading was due to some city driving before leaving town, but was not pleased when it kept going down. The engine also shifted into high gear to maintain cruise control more often than on the original trip.
Could this be due to the belt being too tight? My mechanic said it was 'really tight' and was concerned about it wearing things out, so he did loosen it a bit before I drove away. Or did not having access to ethanol free fuel like I do in OK affect the performance that much? My driving was less aggressive on the return trip, so I doubt that was the issue.
I being paranoid? I've had the car for just over a month and loved it so far. I installed cruise control thanks to CTScott's great tutorial and replaced the fuel sending unit because it annoyed me that something so major wasn't accurate but I'd prefer not to have anything vital to operation break on the car yet!
Thanks in advance for any ideas! (Including telling me I'm worrying too much!)