BamaScoot

I recently towed a boat about 500 miles and since then my "remaining range" and gas gauge go down incredibly slow, to the point where I almost ran out of gas once. Does this reset after a while?

BamaScoot

Update in case anyone searching for a similar problem finds this thread: after 4 complete tanks of gas the computer has reset itself and is now displaying accurate readings.

wkearney99

The service manual indicates there's an option in the PIWIS dealer diagnostic tool to recalibrate the tank. Hook up PIWIS when the tank is empty, save the values. Fill it and repeat. It makes no mention of the system automatically recalibrating itself, but that does not surprise me.

Most systems use a combination of tank pressure, fuel level and tracked consumption to arrive at fill level notifications. This is why you get strange emissions errors sometimes if there's a leak in the fuel cap or other emission venting lines. Was your towing over significantly different altitudes? I've seen that lead to fuel system inconsistencies on other vehicles in the past. Eventually, as you've had happen, settling out on it's own when back to regular driving situations.

nychase

I found out accidentally that the range calculator resets when you do a PCM reset (its in the PCM options). I was attempting to clear the bluetooth connected phones which my PIG wasn't allowing me to do since it detected a change in ownership (no clue....but that was the prevailing thought). Resetting the PCM did clear up the bluetooth issue but also most certainly reset the fuel range and I haven't gotten it back to the 500's since (at the time my wife was mostly highway driving, now I mostly ....uhhh....drive spiritedly).