A discussion I had with my tranny guy

So here it is. Is there any rational reason that would explain why GM enables a PWM high duty cycle for the TCC on a 4L60E?


When I had the multidisc converter put in, it became very apparent that this was occuring when in 1Manual. WOT Logging runs also showed this to occur when in drive/od but it is not as noticable in regard to SOTP.


So what are the technical reasons you can think of? I know it is a simple matter to disable it manually ( and would be nice if we could alter the tables associated with it Ken) but It could be a nice feature to leverage.

Luna

of ALL of the LT-1 A4 programs I have seen the manual TCC setting was set to 255MPH or something of that nature. not be a tottal smart ass but I fairly certain you dont have the rear gears for that. :p

OK first off this is a very wacky problem. You need to VERIFY that this is your issue. Download Steve Coles TTS DataMAster here! (http://www.ttspowersystems.com/dm_dload.htm)
Then report back that you have confirmed that the PCM is rewuesting lockup in 1 Manual :cool:

TAD

Originally posted by TurboSS
Luna

of ALL of the LT-1 A4 programs I have seen the manual TCC setting was set to 255MPH or something of that nature. not be a tottal smart ass but I fairly certain you dont have the rear gears for that. :p

OK first off this is a very wacky problem. You need to VERIFY that this is your issue. Download Steve Coles TTS DataMAster here! (http://www.ttspowersystems.com/dm_dload.htm)
Then report back that you have confirmed that the PCM is rewuesting lockup in 1 Manual :cool:

TAD

Not to be a smartass either (ok maybe a little), PWM is confirmed and well known occurance. There is no debating that it occurs only "why" GM does this. Don't confuse this with the std tps vs speed lockup table either either. We are talking about modulating the TCC with a duty cycle of 90.2% starting around 4000rpms.


Fortunately I have a slight idea of how scan a car and have been using Autotap since it was in beta a while back :)