Easyryder01

I went to the dealership to resolve an issue with my wipers, that they were not working continuously, they would work randomly. Any way while I was there a few things got taken care as in recalls one of them was a reflash of the PCM which I was told don't do it it will mess up the jeep. So i didn't, just had the the motor and the whole mechanics of the wiper replaced. Pretty easy I must say. So a couple of days of go the wipers again stopped working. So I went back to the dealer today told them that the problem did not stop and so they reflashed my pcm. The funny part is that my mpg gained an additional 2mpg ? i don't understand it how is that possible ? Was it wrong before or what ?

sickchilly

The flash just cleared your history. Give it a few tanks and you'll be right back to where you were!

sclan

X2 about clearing your history. I can't find the other thread, but I remember reading that also. Also how the whole ETD thing isn't real time anyway. It is taking an avg and your last fill up.

Hkx3

I disagree. I feel like it is close to real-time. If there is anything about this JK that I feel qualified to talk about, it is the fuel mileage. I bought the Jeep in february, and have since put 12000 miles on it. 99.9% hwy, with 2 or 3 trail weekends thrown in.

I consistently get 20+ mpg everywhere, and attain as high as 23.8 mpg on hwy trips. I run I75 north and south from Ohio.

I have noticed that I can leave the fuel system alone and it will change as I drive each trip, or I can reset it at each fill-up, and it still checks out correct. I check the mileage by calculator every other tank, and have found the computer to be within 2 tenths every time. What you will notice is that if you reset the computer, by holding in the button, it will start off at the last reading it showed. It will then begin relearning. As you drive, it slows down and starts averaging. The longer you drive, the longer it takes for it to show you a real-time adjusted value. Like after 200 miles on a tank, if you hold the accelerator at 100% WOT, for say 2 miles (yes Ive done this, mine shuts down at 102 mph), it will take a second or two to display the new MPG estimate. If you reset the computer, and did this same test, it will show like 10 mpg or something very quickly.

Sorry so long winded... Ive had a lot of time to think about this...

Easyryder01

Just to keep you guys posted the reflash turned out to be a horror because it wound up now making my jk now stop turning over whenever it wants to. I will leave it sitting for 6hrs or less and thats it doesn't want to start like if I left a light on or if something drained the battery who the hell knows now !!!!

treadmark

The mpg reported are average; therefore, I reset it (hold the information selection button down for a several seconds until it blinks), with each fill-up. This way I get the average for a given tank.

rwamf

+1
That is what I do also , mine is spot on with the calculator.

ronjenx

I calculate every tank fill-up. The display's accuracy is too variable for me to have any faith in it.

Easyryder01

You were right sickchilly I am back to the lousy gas mileage that I had before. I guess it was a good mind job while it lasted.

sickchilly

Heh... We'll get along just fine, as soon as you realize I'm always right!