I started making some very minor changes to my truck today to get a feel for my EFI live and got a little confused about my TCC settings. Stock the converter will unlock on the freeway every time I let all the way off the gas, and have to lock back up when I apply the throttle again. I wanted to change that setting so that the converter will remain locked reguardless of TPS until the truck slows to ~55MPH. Right now the TPS is set at 100% for unlocking the converter, and the unlock speed is 52.8MPH in 4th and it still unlocks when I let off the gas. If anyone has a suggestion for a tuning newbie I would appreciate the help.

 

I was thinking about this as well. But, I think if you let off above 55 and then get back on it and the converter stays locked it puts a lot more load on the engine. I was also told that in boosted applications that getting into boost with the converter locked will usually get you some KR. I guess what I'm saying is maybe you dont want to tune it out. PM dc_justin hes pretty good with EFI and always helpful.

 

Cool, thanks for the advise . I am tuning my 2000 truck which is my dd, I was thinking that there is un-due wear and tear on the converter clutch when I have to let on and off at very low throttle/load conditions. I don't really care what the truck does either way, so if the converter clutch will not wear out doing this I will just leave it alone. The truck is totally stock right now. I haven't noticed my 2005 unlocking the converter like my 2000 does, that's why I was thinking about it. Thanks again for the contact.

 

Hm... mine stays locked anywhere above 55 unless i give it more than 50% throttle. I like to ease into the throttle w/ the tcc locked and pretend that i have a turbo and i've never felt any loss of power as in getting kr.

 

It will stay locked once youre above your set lock speed unless you increase TPS past XX% (whatever you set that to as well) What hes was wondering, if I understood correctly, was why the TC unlocks when you let completly off the gas and then relocks as soon as you give it a little gas (if you havent slowed down too much).... If youre in 45-50mph traffic it does get annoying.

 

Exactly! I set my TCC release to 100% tps at 52 MPH because I wanted it to be unlocked by speed only. Since it is not working how I want I will try to set the tps at 50% @ 52MPH to release and see if 100% is just a bad setting.

 

I may have figured something out. I have stock 245/75/16 pinner tires on this truck, I entered that size into the tire scaler and it changed to 13% larger than the stock tune. I also set the tps for release at 50%. I'll see if that changes anything.

 

I have been playing with these tables as well. Logged the TCC today in 3rd while cruising a little over 40 mph. TCC Apply is set to about 40 mph and TCC Release at about 30 mph for all TPs 31.25% and below. Anytime the TP goes below around 20% the TCC goes to off. Unfortunately, the TP is constantly hovering around 20% while cruising at this speed(typical city driving). So the TC just keeps locking and unlocking. This release seems to be based on TP with the VSS being irrelevant. I don't see a table that would cause this anywhere in EFILive.

Also noticed that the TCC enable is constantly switching on and off in 2nd even though TCC engage is disabled in 2nd(all VSS values set to max). Not sure if this is normal.

 

After speaking with joecar a bit about this stuff on the EFI Live forum, the general consensus is that there are likely a few more tables that haven't been discovered yet...

One such example is this, (although it could be purely mechanical)... My TCC is commanded to release at x point, but will not actually release for 1 full second after that point. This is a major pain when driving around in boost at under 60mph. Want to lock the TCC for milage, but if I get on the throttle too quickly, boost builds up well before the 1 second TCC release and detonation sets in...

 

I assume you are using the TCC Throttle Release tables to do this? I have tried that as well with the same result. Now I have those tables disabled again and have been playing with the shift tables so that I get a 4-3 downshift if load goes beyond a certain point(as represented by TP vs VSS). I have the Kickdown tables disabled as well. Seems to be working much better.