Battery Cutoff Question

Discussion in 'Fox 5.0 Mustang Tech' started by 93 SVT, Jul 24, 2013.

  1. Bought a mustang that has a cutoff switch. Is this a problem with mass air cars? If I remember correctly, the computer learns over time and doesnt a cutoff just completely reset the computer every time it is turned off?
  2. I am more worried about hood clearance with the typical top post disconnect. If you are worried about theft, memory and fire, there is a fuse bypass style. Hit the key and the fuse blows.
    As far as learning, I doubt there will be more than 5~10 minutes of relearning you will notice. Not bad for a winter worth of not worrying about old wiring.
    PLEASE Let me know if you find one that fits well!

  3. No... It's not a problem. The adaptive strategy in the EEC makes minor adjustments over time. The longer it keeps values in the KAM the better it will get but there's no earth shattering consequence if it has to relearn each time the EEC is refreshed. Even if the EEC has been chip tuned, the base tune on the chip will still be the starting point.

    Having said that, is it better to not dump the EEC every time you shut it down? Yes. One solution to that problem is to feed one of those 9volt systems through the cigarette lighter to keep the KAM alive. You could even hard wire it in if you like.

    Either way, I doubt that you will see much of a difference in how the car performs. Keeping the KAM alive might show a recordable difference in fuel economy over time.
  4. I would say its fine if the car is not tuned. And if it is tuned, I think it depends on how close the tune is to where it should be. Pretty sure the KAMs will hold changes that are made while the car is being driven. And after driving the vehicle for a period of time the car will most likely drive better. So if the tune Is close to where it should be not many changes should be made, and the car will be fine if you cut the battery.