Only getting between 16-18 MPG since the addition of my HKS and JWT pop charger? And don't say it's my lead foot because tested hard or soft driving provided similar results. I have an 04 6SPD sedan with 27K on it.

 

did you try resetting your ecu. you may be running rich.

 

No I didn't, because I didn't think those minor mods would alter air/fuel ratio. Guess I was wrong.

 

woww.. i cant even come close to 16 mpg.

 

Ok should I consider myself lucky then? I used to do way better than that prior to my mods. Don't get me wrong I love the sound of the mods but I didn't think they would have caused the decrease in MPG

 

I've always gotten about 16-19 with/without my pop and ztube and hks muff. So i think its normal.

 

I average 23-25 mpg, so I think 16 mpg is a wee bit on the low side. I have a 45 mile one-way commute, half local roads and half highway where I do 75-85 mph. No easy-does-it here.

 

Is there some way to tell your MPG from the ECU? Or are you guys just giving estimates on what you're getting off hand?

 

I'm not sure about doing it the ECU way but I use the amount at fill-up divided by the amount driven method. Doesn't get any more accurate than that regardless on what Nav systems will display.

 

I find 23-25 mpg hard to believe with these cars. Even the EPA stated between 17 and 24 so averaging more than the EPA is suspect IMHO. I average 17-19 and if I'm only doing highway at 75-80 I MAY get 22. I have no mods on my car but it iss an X and an auto transmission. If you are getting 23-25, more power to you!

If you need it, here is the ECU reset procedure. I got this from a member when I first got my car in April 2005.

ECU Resetting Procedures

Timing is extremely critical. If it is NOT DONE within the specify time, the ECU will not reset and the Check Engine Light (CEL) will continue to remain ON.
A stop watch or an analog clock with a second’s needle will be useful.

Operations Procedures for Basic reset.
1. Confirm that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.
2. Repeat the following steps (2a and 2b) procedures quickly five times within 5 seconds.
2a. Fully depress the accelerator pedal (HARD).
2b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the CEL starts blinking.
4. Fully release the accelerator pedal (while the CEL is still blinking)
5. Wait about 10 second.
6. Fully depress the accelerator pedal and keep it for more than 10 seconds.
7. Fully release the accelerator pedal (The CEL light will continue to blink).
8. Turn ignition switch to “OFF” position and now you can start the car. The CEL light should be gone.

If the CEL light continues to remain ON, repeat the above steps. Timing is EXTREMELY critical to resetting the ECU.

 

^^^ timing is everything. use your watch to keep track of the secounds. if you time it exactly IT WILL WORK. if you didnt time it exactly it will not work.

 

I don't really use a timer and it takes me 2-3 tries to do it, but it werks!