747 Idle Learn, GM OEM

[Bruce Plecan]

-----Original Message-----
From: rauscher at icst.com <rauscher at icst.com>
To: DIY_EFI at efi332.eng.ohio-state.edu <DIY_EFI at efi332.eng.ohio-state.edu>
Date: Tuesday, November 24, 1998 4:29 PM
Subject: 747 Idle Learn, GM OEM

If this is engine code T, there are numerous updates on the prom
for that application.  I'd investigate that at a dealer, first.  BTW,
I don't show a 737 for that 3.1, what ecm does your have?.
Bruce


 I have a good question regarding the 747 ECM. Does
 this system need to go through an idle learn?
 I ask as I know that there are other GM ECM's that
 do go through an idle learn. While in this 'learn'
 time, the idle is about worthless. The engine will
 stall, sputter, rev-up, rev-down, heck, I almost
 hit the car in front of me during one 'rev-up'.
 If the 747 has an idle learn time, it may help to
 explain why so much work needs to be done to get
 some vehicles to idle properly.
 I now know the manual procedure for the idle learn,
 it takes ~20-30 minutes at idle. Or, like I did,
 a full weeks worth of driving... This is on a '92
 MPFI 3.1L Camaro. (A 1227737 ECM??).
 Thanks, 
  BobR.