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Reformating the ECU

Discussion in '80-Series Tech' started by landtoy80, Jan 2, 2004.

  1. landtoy80

    landtoy80

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    I want to clear the Computers memory. I tried pulling the EFI fuse and that seem to only clear the memory for stored codes.
    When I had the battery off for over a week and I started the motor it started and as it warmed up the idle keep going down to about 200rpm or less an would almost die. I had to drive it several miles before the ECU learned the settings of the EFI and would idle at about 600rpm.
    Short of unhooking the battery, what fuse do I pull and for how long?
    If the battery needs to unhooked, how long?
    I pulled both ECU fuses tonight. I will see what happens.
     
  2. Shortbus

    Shortbus

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    Not sure on a Toy, but I bet if you leave power off overnight that it'll reset. I searched the FSM and couldn't find anything on resetting the ECU. I'd try power off for 24 hrs and see what happens. :-\
     
  3. T Y L E R

    T Y L E R

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    I left my electrical manual at work , but I do recall that when I installed my Truspeed recallibrator I had the battery disconnected for maybe 5 hrs . Afterwards the rpms did their usual quirky relearning phase . I've had the battery disconnected many times on my '97 and several of these times the rpms have taken a few mins to find their place . Each time I believe I have let it do it's thing while at idle ; without driving it . Just reved it some . In any case the battery didn't seem to be disconnected for a great length and the recovery was quick and painless in my personal experience .
     
  4. Wayne

    Wayne Bought by His blood, kept by His power

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    landtoy80,

    I think Cdan addressed this on another thread some time ago when asked about an irratic idle. As best I can remember, the ECU clears after two hours without power (unhooked battery) and can take as many as ten to twelve starts (with normal driving after starting) for the ECU to relearn and establish the 600 RPM idle.

    I don't know if pulling a fuse on a Cruiser will accomplish this. I own a '98 Cobra Mustang and I have to unhook the battery to clear the ECU.

    Wayne S
     
  5. landtoy80

    landtoy80

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    Well, removing the two ECU fuses for 10hrs did nothing.
    I was hopping to not lose my (wifes) radio stations preset on the radio.
     
  6. robbie

    robbie Guest

    Well guys the 91-94 computers are different then the 95-97 computers. removeing the efi fuse will clear the the codes for both types (OBDI verses OBDII). Pulling the battery is the best method for both computers to get fully cleared. You really should only have to disable the computers for 10-15 minutes for this to happen. Later robbie
     
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