I'm having sinister performance tune a pcm for my 1996, I'm having them add fuel trim and a couple other tweaks. I wanted to have my torque converter lockup earlier, at 3rd gear maybe. They told me the 1996 pcms have a software malfunction where it won't won't properly, at least that's the case for bonnevilles which they tune alot, he said Riviera might or might not be affected has anyone tried doing a 3rd gear lockup for around town driving?
