Black8Banger

iTrader: (9)

While cruising if I let completely off the gas, the TC will not unlock. Instead the car has major surge back and forward. I have to tap the brakes to get the converter to unlock. When I release the brake, the TC locks back up and the surging continues! What is going on here? Do I need a new converter? Is there something wrong inside the tranny? This converter keeps locking up when it shouldnt!

Its a 99 LS1 37k miles with 4L60E
228/232 Cam
TCI 3200 Converter

jimmyblue

iTrader: (11)

How do you know it isn't doing what's programmed?

Or, if it hasn't ever been programmed, that's the likely
trouble. Lot of mods on there, your deceleration fuel
cutoff is a likely bad boy but it may also just be screwy
low-MAP, low-RPM mixture supplying the jerk and the
throttle follower supplying the air. But you can tell the
PCM to release at whatever MPH/TPS you like. The
stock TCC settings don't play so well some of the time.

Black8Banger

iTrader: (9)

The car been dyno tuned so I wouldnt think tuning would be an issue. I have talked with the guy who tuned the car and even he couldnt think of any type of problem associated with the tuning.

Kevin Winstead

The torque converter will only lock up and unlock based on commands from the PCM. Since it does lockup properly and then unlock when you tap your brakes, it sounds like a programming issue.
Kevin

samz28

sounds like crap tuning to me. you don't tune a torque converter on the dyno, You need a good bit to street time to get a big cam to lock up low and not surge.

Ragtop 99

iTrader: (7)

That's cam surge.

Look at the lock-up tables from the factory. The PCM is programmed to keep the TC locked during coast down to pretty low speeds. You may want to change your lock-up tables or see about tweaking your tuning below 2000 rpm.

94form2000z

iTrader: (10)

definite programming issue.

SmokingWS6

iTrader: (1)

ditto. definately programming issues. the pcm will not command the converter to unlock wile at 0% throttle. It'll base it off mph. mine will unlock while coasting down at 35 mph. unless I hit the brakes. Timing issues might need to be addressed to correct the cam surge.

Black8Banger

iTrader: (9)

you guys are good, I talked with my tuner and he said definately a simple computer problem. He said he can fix it no problem!
.....Im just glad it wasnt my tranny going out....yet.....
Thanks for your help!