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Old 10-17-2018, 03:35 AM   #102
geraldjust
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Quote:
Originally Posted by Sportsguy83 View Post
Swapped car with Motec. As far as I understand it, the fuel level calculation is done outside of the Motec. The first tank of gas after the swap, the car read properly. My theory is that this happened because all throughout that first tank of gas, we removed/reconnected the battery a bunch of times, always "recalibrating" the gauge and thus it read correctly up until the end.

Subsequent tanks run out at 1/4 tank. If I disconnect the battery and reconnect it, it seems something gets recalibrated and the fuel gauge reads properly again, but it only lasts until I refill then it goes back to running out exactly at 1/4. I tried opening both sides of the tank to see if I could see anything wrong (the fuel gauge worked flawlessly for 5 years before the swap) and nothing seemed out of sorts... I believe also that if I clear codes on the other car ECUs (ABS/A/C, etc..) (the stock one is not there anymore), the fuel gauge starts reading correctly but again reverts back once I refill it.

Do you have any ideas? Thanks.
Ohh! hmm.. Well i know why. Has it been fixed yet? Did someone did the swap for you or was it a kit?

Anyways. So... long story.. when removing power to the cluster the cluster looses its calibration memory so it doesn't have anything saved. This calibration is the "MAX" and "MIN".. It needs this as part of the EVAP system. So on first reset, cluster only uses the Resistor level sensor only to calculate fuel level. Once it goes into one fuel cycle .. from Full-ish to empty to back to full.. then its fully calibrated it starts using other data bits coming from the ECU saying its fuel usage...Its part of your "fuel economy" in your cluster. By any chance is your fuel economy working? That is a special data that Each engine kind is a bit different.

Wait so besides in your swap you get ABS/ AC errors and stuff? Did you wire those in or was that a kit?
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