Cadillac STS-V Series ForumForum specifically for Cadillac STS-V series discussions. With 469 horsepower, this is the most powerful production Cadillac ever made.
If you have purchased a D3 Stage 1.5 ECU box for your STS-V and have a Service Engine Soon Light on due to fuel trim code(s), D3 now has a new tune available that will correct this. We are doing warranty exchanges on all defective Stage 1.5 ECU boxes. Please contact your sales rep for more information.
Also: please note there is a revised ECU mounting location that puts the ECU box below the air filter in the area just behind the driver’s side fog light. This will help to prevent any ECU boxes failures due to excessive heat. Please make sure the box is mounted just below the frame rail and not down at the bottom where it could be exposed to water or road debris.