A_W_O_L

iTrader: (2)

Just like title says...It's my sisters 98 V6 Camaro~140,000mi...I had to drive it somewhere the other day, and asked her about it, she never really noticed (surprise surpirse) so i dont know how long its been doing it. SES isnt on...Im going to grab it from her tomorrow while she's at work and drop by autozone and see if there are any stored codes.

Running down the road at constant throttle on flat\downhill ground it doesnt lock.... if you start dipping into the throttle, it will lockup...then as you back out of it and hold a constant speed on flat/downhill ground it will unlock again. if you start up hill or dip into the throttle (putting engine into a load) It locks up???WTF?? Any suggestions?? It's full of Fluid BTW.

01WS6/tamu

iTrader: (37)

The TCC bore in the valve body is more than likely wore out. It is not supplying enough oil pressure to the tcc to hold it locked under load. Chances are that it get prgressively worse as drivetime and TFT temperature increases these are the usuall sign of death. The best thing to do is a complete rebuild before it completely dies and you can save an assload of money on parts the will be dicked up. Chances are that by now it has probably damaged the converter. The route is to either replace the valve body or transgo makes a tcc upgrade kit that puts an oversize piston in it's place. It is a little more work than it sounds though. Or just put in a gm SRTA trans with a 3 year 50,000 mile warranty and call it good.

A_W_O_L

iTrader: (2)

hmm....But it LOCKS under a load....If you start out from a dead stop and give it about 30-40% throttle (just a guess...point being that im not getting crazy, just accelerating) it will shift 1-2,2-3...convertor locks, 3-4 just fine..converter still locked...when I start getting out of the throttle to maintain a constant speed, coverter UNLOCKS. IT's when there is very little load on the drive train that the converter either doesnt lock, or unlocks.
Im not trying to beat a dead horse by explaining it again, but I thought I would be a little more clear as to what it was actually doing. Would a worn out TCC bore still cause symptoms like that? Dont get the wrong idea, I dont question you knowledge, I just didnt know if I was explaining it well enough, because if it will lock under a load--accelerating conditions, then I would think that the tranny is in good enough shape to withstand lockingup under a lighter-load situation like maintaining constant speed. I tried driving faster to see if the change in engine speed had any effect on it ( maybe the pump in the tranny is going out?) but it didnt. I appreciate you input...Im off to get it scanned...
Charles

01WS6/tamu

iTrader: (37)

After re-readingI think I missed the whole point of the first question. I have ran into a few 4.3' autos in s-10's at the shop that did the same thing. I believe it is simply the programming in the pcm. For the trucks they have an update that delays tcc lockup till about 55 or so to prevent tcc cycling like you describe. Sorry about that earlier. But if it ever starts doing that you know where to look now.

SmokingWS6

iTrader: (1)

Excessive missfires also will cause a converter to unlock, or never lockup. However that should produce a SES light.

Flals1

My converter is doing the same thing. I just had a dyno tune and it was fine before that and now at part throttle when I hit 30 mph the converter progressivly locks up and feels like crap. On full throttle the car seems alot better but still progressivly locking up instead of a quick lock up. Could it be the TCC lock up selinoid? I took my car to a tranny shop and they said it might be the clutch is shot in the converter(TCI2800). I would hate to buy an new converter to find it might be something in the PCM. The tranny shop said to raise the TCC lock up to 50mph but my tuning guy said it would probably do the same thing just at a different speed.

A_W_O_L

iTrader: (2)

Well I got it scanned yesterday (didnt post it right away...dealing with school issues) There were no stored codes

Flala1- id guess since it started after the dyno tune, it's probly Tuning related.

SmokingWS6- I was thinking the same thing

01WS6/tamu- no worries, just trying to work through this. Would there be a reason for it to start cycling (pcm-wise)?? The last time I drove it(It had been about year...year 1/2 ago) it was fine.

With 140,000mi i could see where it could be the lockup solenoid...does anyone know how many miles it typically goes out in? (TCC lockup seloniod...or any of the other components involved for that matter)

Thanks guys for all help so far...Whatever ends up being the culprit I'll post up incase someone else is has the same problem in the future. I'm going to have her pick up some tranny fluid, gasket, and a new filter...see if that fixes/helps it.

A_W_O_L

iTrader: (2)

The oil doesnt have a burnt smell, it still has good color, and I dont see any metal flakes in the oil on the stick.

01WS6/tamu

iTrader: (37)

The only way to for sure tell what is going on is with a good scanner like a tech 2 etc since the vehicle does not have a tuning program to let you view the parameter. The only thing I could say is get a tech 2 go to tcc data in the trans data scetion and look to see if the pcm is commanding the tcc to lock un-lock when it starts acting up. If the pcm is commanding it could A be normal due to programming or the pcm thinks something is not right. Also there is a data section that shows tcc enable and then slip speed.
For instance scanner will say TCC enable yes or no, TCC commanded lock up in percent. Then it will show slip speed. If it says locked, say 95% and the slip speed should be within about 3-5 rpm if the converter is function correctly. This is one that is real hard to diagnose unless you have a scanner to monitor it and know exactly what to look for during the drive cycle when it occurs.

Flals1

I had the tune checked out and it's doing the same thing. I have noticed it only does it when the car is warmed up approx. 10-20 min. after initial startup in the morning.

I just ordered all new electrical solinoids for the valve body. The helms manual is saying it might be one of them. I am going to try them out. The next step is a new coverter. The tuner and the tranny shop seem to think its the converter. They said TCI sucks so I ordered a YANK 3600. I guess I'll figure it out one way or another.

Thanks