help! transmission shifting problems!

[Brian Harper]

Some dumb questions . . .

I just had my TCC solenoid replaced and now the tranny is shifting up through the gears too quickly under light throttle and the TCC is locking up as soon as the tranny shifts into third at about 25 mph. It also shifts into 3rd about a second or so after shifting into 2nd gear. I tried the brake test on the TCC lockup and it passes the test no problem, even in third gear going 25 as above. Everything seems normal when driving under harder acceleration.
My questions are: what actually determines the shift points? Is it fluid pressure, or the ECM? Also, is the TCC lockup solenoid fed 12 Volts from the ECM via the ALDL connector F? If so, can I use a voltmeter and measure when the ECM is calling to lock up the converter? Any other troubleshooting suggestions? The car / transmission are all stock with 50 k on the odometer. Any help would be greatly appreciated.
Thanks.

 

[MeanBuicks]

Readjust your TV cable first and see what happens. The TCC system has nothing to do with shift points, the TV cable has just about everything to do with them.

 

[Brian Harper]

Well, i adjusted my TV cable as per the instructions on gnttype.org. Originally I was showing 5 notches on the TV cable, so I adjusted it up to 6, then took the car for a test drive. The shifts are definitely higher and firmer, and the downshifts come in sooner as well - almost too much so. I think I will adjust the cable back to the original setting. The TCC is still locking up as soon as I hit 3rd and still well below 45 mph, but its passing the brake test fine.
Any ideas? I don't really have a clue how these transmissions work, so any help or advice would be greatly appreciated.

 

[NC87GN]

Your chip also has TCC lock-up programmed at a certain mph. I am looking at the stock 87 chip and TCC lock-up 3rd gear is 23mph.. 3rd gear unlock is 22mph. 4th gear TCC is 39mph and unlock is 37mph. You might wanna try an aftermarket chip with higher TCC values in 3rd and 4th gear. HTH

Mike Banas
87GN

 

[Brian Harper]

Update . . .
Well I adjusted my TV cable back to the original setting, with 5 notches showing. The tranny is still upshifting pretty early and the TCC is locking up as soon as it hits 3rd. The car really dogs along until the revs get up a bit. As well, the transmission seems to "clutch and grab" when coasting down in speed in second and is really jerky if you touch the gas at all, as if there is no slip or give to the transmission. Think of it as driving a standard in second gear and jabbing at the gas pedal. The car behaves fine up in third and fourth other than the TCC locking up too early.
I'm getting desperate for advise here. I don't want to drive the car anymore in case I break something. Any help would be great.

 

[transfixleo]

To adjust the TV Cable skip the book method and do this: Press the 'D' shaped lock button on the adjuster and loosen the cable setting (The black housing that the metal cable is in will move forward). Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the 'D' button and pull the cable casing (the black tube) back as hard as you can (putting maximum tension on the metal cable) and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable casing so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting, which is theoretically what the GM method does.

 

[Brian Harper]

Well, that definitely helped. Thanks for the info. The shift points are back to normal. The tranny is still jerky feeling in second gear though. Maybe the universals are going, but it just feels like the transmission is still grabbing.