I'd gladly run a search here folks but my hand is in bandages after I put a pry bar through it working on the car and had to get stiches, so my typing is very slow and me and the mouse aren't getting along well right now. EDIT: Searched, looks like everyone else having problems with this their lockup is completely gone or very intermittent, and they've also had the converter for a while. Mine is BRAND NEW and its locked about 50% of the time and unlocked about 50% of the time. Details...

Previously: TCS (Crap Company) 3200/2.5, lockup felt like a 5th gear. VERY solid, noticable lockup. Once locked, it wasn't coming unlocked unless I wanted it to or I dropped to a low enough speed to unlock it. It locked like a pitbull's bite and didn't let go. I love this and want it in all my converters.

Now: TCI 4000/2.7, lockup is VERY soft and doesn't happen immediately once I hit cruising speeds like the TCS did. It also randomly unlocks for no reason at all. I give it a very little bit of pedal and notice it's unlocked itself on me. Sometimes under mild acceleration it will lock while I'm still speeding up.

Lockup/unlock is so soft I cant even feel it and can barely hear the exhaust change note. I've driven it about 50 miles, two WOT runs (shifted fine, felt great), highway and interstate speeds as well as around town driving. We did put fluid in the converter before installing it. Other critical mods are an MTI T1 221/221 cam. The cam and converter went in at the same time, so I never ran the cam with the TCS to see if it changed things.

Fluid level looks good. Not sure what tuning I need to do here if its related to tuning. The converter feels great at WOT and its not near as loose as I was thinking it was going to be. This lockup thing is the only thing standing in the way of this being a great converter. I really liked the solid lockup of my TCS, that 5th gear feeling. If my TCS would have been a perfect medium of 5 between soft-as-a-baby's-bottom lockup (1) and neck-snapping-bone-jarring lockup (10), the TCI pulls a solid 1.

Any suggestions on this folks? Could it be tuning related? Did I get a bum converter? Thanks a ton for any help. I'm dying to drive the car but I dont want to overdo it with the converter unlocking and cook my transmission.

 

Your 4000 is probably a 9" converter? Small clutch.
Try setting the TCC offset table to 98 across the board,
this will give you the hardest possible apply for the
available line pressure. If you need more than that your
only option is to up the line pressure at light throttle by
lowering the force motor current. See recent posts here
(TCI 3500?). You probably also want to play with the
lock/unlock points to make it plain give up at torques
where it has no chance of holding. But you want highway
and slight grades to be locked solid to that sets what you
have to do with the force motor. Unless you have a means
of tailoring the commanded line vs load, which I don't.

Random unlock is most likely misfires and with a small
converter you want to raise those thresholds at least
some, many folks say to outright kill it but I figure the
warning serves a purpose so maybe just double or triple
the fault threshold as a start.

This all sounds easy enough but you need the tuning
tools of course. And to spend some quality time on the
road logging the results & fine-tuning for something that
makes you and the car happy.

 

HPTuners v1.5 I believe is what I have at my disposal (friend's program). Pretty sure random misfire is cut off because the cam was throwing a code (P0300 maybe?). I'll check it tonight though when I go back over. I'll also check that TCC offset value and see what 98 does for me. I had HP Tuners automatically scale the shift points for the 2.73->3.42 swap and that lowered my lockup speeds in D and OD about 10 MPH (D was 40 and OD was 50ish, now its D is 30 and OD is 40ish). Might need to bump them back up if I can find the values in HP Tuners.

TCI is a 9" I believe. I suppose the cam/converter combo just needs some tuning to get it working right.

 

We messed with random misfire but may not have done that part correctly. TCC Offset was changed to 98 across the board. Still no luck. Its locking and unlocking at will. The TCS would not lock until I basically wanted it to (hit a speed and maintained it with little pedal input) and would unlock when I wanted it to (give it a quick stab of the gas and it would unlock. This TCI is doing whatever it wants. Its even locking randomly on part throttle acceleration and bogging the car down. I'm lost here folks.

 

i have the same problem with my tci 4000 converter with the random unlock/lock, but mine is also blowing the eng ctrl fuse, and throwing codes for all of the trans solenoids.

 

I'm not getting any of that. I'm going to have some professional tuning help this week and I'll flash the new tune in this weekend to see if it works. We're thinking cam + big stall is adding up to random misfires doing funny stuff to the lockup.

 

You dont just turn off the code. Raise the enable/disable temp to 141C/142C

That'll cure that problem. Also turn off lockup in third. With the 3.42s you dont need it at all.

Raise your lockup speed in fourth to about 60mph. This will reduce strain on the clutch. That should help alot.

Only if the above doesn't work should you play with the force motor current tables imo.

 

I'm not sure what was changed in the professional tuning, but we've got a tune we'll flash in this weekend and see how the car drives. Big thanks to Scott @ Gen3Performance (gomer) for the help. Looking forward to having him do a full blown tune on it and get the car running to it's full potential. Hopefully these tweaks he's made will be just what the car needs to drive right so I can get it down to Birmingham.

 

I dont know what in the world gomer did, but my car is a dream to drive now. Idle and part throttle are great. Its awesome at WOT. The biggest thing is the lockup though. Much more positive (4 out of 10 on firmness of lockup) and it doesn't come unlocked unless it's supposed to (low speed, go pedal ). Tuning was most definitely my problem and Scott got me taken care of. Can't thank him enough. The 4000/3.42 is still a LITTLE loose, but nothing too extreme. VERY happy with my converter choice now.

 

Cool man, I was thinking that would fix your problem! Enjoy that thing now.. and start saving for some new rear tires

 

That fund has already begun. Going to need some Nittos on the street and my BFG track tires are up for sale. Going to need some ET Streets to hold this thing. Hell yes.

 

I have the same problem with my conversion in a 69 Camaro with a TCI 2,800 stall converter, cam/head package. Just drove the car on a 2,000 mile road trip. The on/off TCC drove me NUTS. Plus, once in a while it will just upship and go to lock up during aggressive acceleration causing the car to bogg like a mother lover.

Talking to my programmer now about re-working the PCM.

My question is, why would this happen? You mention changing the temp settings. Does the trans run hotter or cooler with the 2,800 stall?

My buddy is a GM tech and put the tech II on the car and verified the PCM is actually enabling/disabling the TCC command. It baffles him and he has tried to find info on all the input required to make the trans do this. He thought it was temp related and told me maybe the TCC program in my PCM right now is more stock and is looking for higher temps. My engine tends to run right around 185, I have no idea what the trans is running, but it is hooked through a stand alone cooler on the core support.

My wife wants us to take the car on a quick trip to Tampa 7/23-24 but I don't want to run it anymore until this is cured. Running out of time.