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maintaining e38 ECU memory

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Old Mar 17, 2023 | 03:39 PM
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Default maintaining e38 ECU memory

Gents,
I have a track car running a GM E38 ECU. I have a battery isolated switch in the car, and when the car is parked up, I'd like to isolate the battery without dumping all my long/short term fuel trims etc. I can plug a 12V powered OBD2 module into the port to maintain voltage, but have no idea what kind of battery capacity I need to maintain memory for a few weeks. Any ideas/experience with this?
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Old Mar 17, 2023 | 03:45 PM
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The ECU uses next to nothing of the battery.
Use the isolater, but run a seperate small wire from battery to the ECU only, IF there's a way to effectively do that.
Just brainstorming here... on what little brain is available.... lol
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Old Mar 17, 2023 | 06:10 PM
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This isnt what you want to hear probably but if the tune is dialed in it wont have any issues having battery unhooked. We have battery disconnects on tons of cars and its never an issue. We also typically dont run LTFT on something we race.
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Old Mar 18, 2023 | 08:56 PM
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Originally Posted by minytrker
This isnt what you want to hear probably but if the tune is dialed in it wont have any issues having battery unhooked. We have battery disconnects on tons of cars and its never an issue. We also typically dont run LTFT on something we race.
Any challenges with throttle learn DTC's from getting on the gas too soon after start up after a "cold boot" ?
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