View Single Post
  #3  
Old 11-09-2022, 06:47 PM
Z06vette's Avatar
Z06vette Z06vette is offline
Senior Member
 
Join Date: Nov 2006
Location: Pensacola, FL
Posts: 453
Thanks: 0
Thanked 7 Times in 5 Posts
Default

When I first made the transition from the LS1 411 ecm to the E38 style over the course of man builds, I found that trying to overwrite a file on any of the E38/E67/E40 ecms bricked it. In the old 411 you could make the file anything you wanted. At least in my experience, once its overwritten its done. Now, I have not ever done anything that had the GMPP ecm. And you can't even change them from manual to auto, etc. It acts like it changes it, but its not actually changing the file. This all started when I had a 6 spd manual LS3, but the E38 was from an auto. Speedo would rear 158mph even sitting still. And it had some odd backfiring on de-acceleration. After a ton of research I basically had to wire in a TCM and use its output for a correct speedo signal. I went to a manual file ecm and everything was perfect. My buddy is a 20 yr tuner. Also, if you have dakota digital gauges using a BIM module, We have found they need to be unplugged from the BIM to be able to access the ecm file.
__________________
69 RS LS3/T56
68 firebird vert LS1/4L60E
67 RS LS2/T56
Reply With Quote
The Following 2 Users Say Thank You to Z06vette For This Useful Post:
130fe (11-10-2022), dhutton (11-10-2022)