Last weekend I made a 4 hours trip on the highway. Before I leave I filled up the gas and reset the trip odometer and the MPG. After the trip...my MPG is 29 mpg I don't think it's read right. Even when NA, I don't got that kind of gas milage. Something must be wrong here.

 

Nothing strange there. My mpg actually went up after I had the turbo installed.

 

15-17 city
19-22 hwy

 

well thats good considering the gas prices are still high

 

please explain..unless you are driving miss daisy...that is utterly impossible!!!

the factory mpg gauge gets all messed up when you make the modifications involved with forced induction...mine says i'm getting like 40mpg...hmmm, yah right
depending on my driving:
14-24mpg

 

yeah my car is saying like 30mpg. weird as hell. i wonder why i reads so high

 

you probably have a piggy back system that is lying to the ecu, meaning you are putting more fuel into the system than the car knows about. some of them work off the throttle body positition, but since this car is drive by wire..... plus, you have larger injectors than the car knows about.

 

Aaron is correct....the larger injectors with correction make your MPG gauge useless. It will always read way higher than actual. The stock ECU thinks you are pumping less fuel into the motor, when in fact...you are pumping the same or more....but not less.

 

My computer says 24-29 after I changed to the 440's. It was pretty reliable before the injector upgrade and flash.

 

I do my gas mileage calculation the old-fashioned way. Just take the number of miles in the trip odometer and divide it by how many gallons you added to fill up.

When I stay out of boost...I'm getting the same gas mileage I used to get N/A. When I'm in boost...it gets MUCH MUCH worse. But it's so much damn fun.

 

I don't think I could go through a whole tank without boost! I can't even go 1/2 mile without it.

 

I agree

 

Mine says 34-36 usually on the highway but I really get more like 21-23. and 22/35 (.6286) is very close to 280/440 (.6363). Not sure if this is just a coincidence or this is how the computer is reading it. It is reading as if the stock injectors or only open so much which makes the reading much higher for gas mileage than the new injectors that flow more when it is open equally. Thats just my theory

 

Well since I just got my car back after a 4 month seperation, and I have a new built motor and greddy tt kit, I am getting about 180-200 miles to the tank which is about 9-10mpg. I know which mod contributes to my poor gas milage......My lead foot!

 

I usually get about 18-20 mpg if I cruise, and about 12mpg if I beat on it.

 

man, i'm going to have issues when i go FI... cruising on the highway i can get 33mpg, but in the city i'm at 12mpg or so... when autoXing, i average 3.5-4mpg!

 

I just know mine went up about 1mpg since the install. I wasn't aware that gauge was all f'kd up after a change in the injectors. Of course, I live in an urban area where stop lights are constant. I don't dog the car by hitting boost at every light. The only time I really get on it is when I'm passing someone or on the weekends when I take it out and have fun.

The car was a daily driver at first but not anymore, in the last 2000 miles I'm showing 18.1 mpg, which is at light-to-light traffic for most of it. My average speed is still 19mph (most of the time sitting at a damn light)

I'll have to run the car dry and calculate it the old fashioned way, I guess.

 

You don't need to run it dry...

Next time you fill up your tank write down how many miles total on your car on the receipt and store it in the car. Then the next time you fill up do the same thing. Then you can just subtract the numbers to figure out how many miles you went from the first fill up to the second fill up and look at the second receipt to see how much gas you used.

 

or just reset one of your trip odometers when you fill up and divided the mileage by the gallons of gas you put in.

 

Or use the odometer.