JST8A5.0

After my vig 3200 install, at 35 mph, while driving slow, the TC locks hard. If I drive faster it'll lock a little higher like 45. This is what my concern is. I go from like 3000 RPMs to like 1100. And it won't unlock until I drop below 35 or I give it enough gas for it to down shift. It's real annoying when going through neighbor hoods and on friggin' I-95 in rush hour. Also at around a leisurely 15 mph, I give it gas and it BANG downshifts to 1st or something then BANG upshifts to where it should be. It just doesn't seem normal below 50 mph, but after that, sweet. It's more of a stop and go problem, not an acceleration problem. Please enlighten me.

RedSlpZ

"I just replaced my torque converter now it unlocks randomly" FIX

--------------------------------------------------------------------------------

Ok, I hear this issue all the time, its time for a sticky.

Guys/Gals with automatic cars listen up!

When you switch to a nice high stall torqe converter, the PCM can no longer use its default program to determine engine misfire. Here is the reason: The corque converter is part of the rotating mass of the engine's rotating assembly. When you reduce the wieght of the converter you are reducing the amount of Flywheel effect. The computer's stock tune is very sensitive to this rotating mass. Therefore the computer can no longer accuratly read engine misfire.

The computer has a logic routine that has certain perameters to be met before the computer locks the TC. They are (as far as I can tell):

1. Throttle position vs. MPH (normal cruise tables)
2. Engine coolant temperature > ???F (not accessable in edit)
3. > 40-50 misfires per 200 revolutions (not accessable in edit)
4. TPS = WOT

After these parameters are met, the computer waits 4-5 seconds then locks the converter.

So, for this thread the number three is the issue. Now keep in mind this is NOT code based. If you disable code PO300, this problem still exists, cause it is only looking at the current misfire count. there are only two ways (in Edit) to prevent these faulse misfires from affecting the TC lockup:

1. Set the misfire activation temperatures to 141 and deactivaion temps to 142. This is the easiest method, but its drawback is the complete disabling of the misfire detection/trouble shooting.
2. This method is more trial and error, it involves adusting the time delays of the misfire program in edit for the various ranges of detection. I personally don't use this method, so someone who does feel free to chime in here.

After disabling the misfire detection, barring any mechanical failures, the person should have little to no issues with TC lockup. I hope this helps, please feel free to direct people to this thread if you see they are haveing a TC lock up issue after installing a new torque converter.

Ryan K.
LS1 Edit Beta Tester




Basically Go get a tune. Hope this helps.

BubaGumpShrimp

iTrader: (1)

i have the random unlock issue due to my new fuddle and i know what to do but i think his problem is a different one and i think i know what it is but need more info on the car.... JST please tell us everything you know about the car, i say this cause your post count is 2 and from that im guessing you bought the car used so the previous owner might have installed a shift kit or messed around with the programming. If your the original owner what have you done to the trans and was there any programming done to the car...

Kenafin_02TA

Agreed...his problem isn't random unlocking. From the info you gave it sounds like it just needs to be tuned. It sounds like stock programming from how I remember mine acting, but it's been awhile. But as Buba asked, more info please. Since you say "After my vig 3200 install..." I'm assuming that you had the car when it had another convertor in it. Was it a stock one size one or some size aftermarket? Has anything been done to the tranmission? (shift kit, any kind of rebuild?) Any tuning/programming done to the car's computer? (What year car btw?)

I'm making some assumptions here, but it sounds like you went from stock convertor & tranny to a vig 3200, still have stock programming and it sounds like you just need someone to do some tuning to adjust shift points, lockup points, etc. Giving us more info though will certainly be helpful.

Also, when you say she locks about 35mph, do you have the shifter in 3rd (D on the pontiac) or D (OD on the pontiac)? I have mine tuned so she'll lock at ~35-37 mph in 3rd gear (so she's just over 1500 rpms) and then kick the shifter up to 4th once I know I'm over my 4th lockup point (~50mph). For me, it works better doing it that way with rush hour traffic on 95..helps keep the heat down and saves some on gas since the convertor is locked more. (I also have a built tranny, I don't know about doing that on a totally stock one..)

One final thing, just out of curiosity, I see you mention 95, what state are you in?

SSCam99

Okay, please be patient with me because I'm new at this. I also don't mean to break into his post, but I was just on here searching for a similiar problem I'm having! Less than a week after I put on my Fuddle Racing Torque Converter on I noticed a "vibration" in the transmission shift at 35 to 45mph. (It has also occurred one time in the 65mph range.) Will I need to have a tune to correct this?

Is this something that could cause transmission problems and therefore I should do IMMEDIATELY?

I can't tell you guys how thankful I am for your help!

BubaGumpShrimp

iTrader: (1)

sscam99 do you feal a vibration when the converter is locked up and you give it a little gas to go a little faster if so you have the same problem that i do with the fuddle, in a way its the converter cause its a 10" size and the clutch is much smaller than stock and also made of a different material.. Since its smaller it will slip more and since its a different material it doesnt slip quietly, kinda like when your stoped at a light and you let up on the brake real slow and inch forward--you get a vibration--same thing is happening in the converter. The stock program needs to be changed also cause the tcc apply pressure at lite throttle isnt enough to keep the converter from slipping(note you can only raise the pressure so far-your not directly raising the tcc pressure, you are changing the line pressure which in turn raises the tcc pressure by a certain percent not equal to the line pressure as im told..) Jimmyblue on this site is pretty good with this so search for threads by him or pm him.. I havent reprogrammed my pcm yet for the slipping vibration..so i dont know lol

JST8A5.0

Ok, sorry for not giving all the info. I bought the car about 3 years ago. I got it from a guy who was kinda on the hush side of giving me info. The car was really clean, no nicks, dings, garage kept, basically mint with 30k on it. Free mods were done and maybe some hpp3 tuning and 160t stat. I am not 100% sure about the tuning thing. But as for now, I installed the vig 3200, tsp lid, and corsa cat back. By the way, my wife bought me the stall and lid. Yeah, I am very thankful for having a wife that enjoys the sport with me. My best time in the 1/4 is 12.8 with a 1.78 60 ft on regular nitto 555's. Oh yeah, the car is a 2000 ws6 a4. These are all the mods I know of on the car. Thanks for all the help. One more thing, in 3rd the thing locks up at like 25, but the rest of what I listed was in od.

On a side note, kenafin, did you used to live in woodbridge? I have seen you a few times in the T/A and I have a friend named Jonathon that used to know you, if you're the same person. Thanks again for all the help.

Kenafin_02TA

Never lived in Woodbridge. I've been down there a few times because a buddy of mine used to live there. Don't know of any Jonathon though..