Trans problem: dealer can't find. Maybe we can.

My wife's car a 99 gt w/ 55000 miles on it has an erratic trans problem.

Doesn't make a difference if the car has been running 5 second or 5 hours, how hot or cold the outside air is, trac control on or off, what gear it is in, cruise on or off, or the humidity. It just does this whenever it feels like it.

When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up.

The first trip they put the updated valve body in it and the problem still exists.

I've heard something about the PCS solenoid causing somewhat similar probs. Could this be it.. I don't know alot about an automatic.

Any help would be great, I don't want to get rid of the car but I don't want my wif to be stranded either.

"When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up."

To me that sounds like the torque convertor messing up. Trying to decide if it wants to unlock or lock, thats why it goes away when u let up on the gas or floor it.

Mine has done this before also. I just had a 2200 stall torque convertor put in and when in forth gear when the convertor is locked up and I try going up a incline without giving it more gas the car will serge, as if I was taping the gas pedal repeatedly.

I have 2 different PCMs and it only does this w/ one of the computers. See if the shop can monitor the Torque convertor w/ their TECH 2 while driving and see what it says.

The PCS (pressure control selonoid) is also a very common problem w/ GPs

Try www.clubgp.com see what some others might think.

Hope this helps alittle.

that's weird to read this. that is the exact problem that started with my car today. i had to limp home at 50 mph on the interstate, which was a 50 mile trip. i dreaded every hill i came up on because it would just shake so badly..like it was slipping then grabbing then slipping again(violently). i nearly didnt make it to the dealer before they closed. they didnt have enough time to check it out but they said it could possibly be the torque converter or the solenoid you talked about. i'll let you know what they say it is when they call me back. im sure it's the same problem you are having. it sucks. i only have 110,000 miles on it.

what would make the torque converter go bad? would it be too much power? because i have a good bit of mods. just wondering

that's weird to read this. that is the exact problem that started with my car today. i had to limp home at 50 mph on the interstate, which was a 50 mile trip. i dreaded every hill i came up on because it would just shake so badly..like it was slipping then grabbing then slipping again(violently). i nearly didnt make it to the dealer before they closed. they didnt have enough time to check it out but they said it could possibly be the torque converter or the solenoid you talked about. i'll let you know what they say it is when they call me back. im sure it's the same problem you are having. it sucks. i only have 110,000 miles on it.

what would make the torque converter go bad? would it be too much power? because i have a good bit of mods. just wondering


HALLELUJAH

You don't know how many people have said "Huh, don't know that's weird". Its nice to know that someone else has the same trouble, I'll keep checkin post to see.

i know what you mean HALLELUJAH. i was gonna post on here to see what everyone thought, then i saw your post..what a coinsidence! my dad is mad because he thinks it's the mods iv done. hell, it's a 98 model with a good bit of miles on it--it's the first real problem iv had with the car and iv had it almost 4 years. im gonna show him what you and ripn12s said so he'll know it's not something i did. hopefully the dealer will call soon so i can let you know.

With that many miles I wouldnt expect the trans to last much longer. You'd be surprised what little it takes to kill these transmissions.

As far as what kills a torque convertor, I'd have to say heat and general wear and tear. I destroyed one when the input shaft that is connected to the TC snapped and banged up the tc.

"When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up."

To me that sounds like the torque convertor messing up. Trying to decide if it wants to unlock or lock, thats why it goes away when u let up on the gas or floor it.

Mine has done this before also. I just had a 2200 stall torque convertor put in and when in forth gear when the convertor is locked up and I try going up a incline without giving it more gas the car will serge, as if I was taping the gas pedal repeatedly.

I have 2 different PCMs and it only does this w/ one of the computers. See if the shop can monitor the Torque convertor w/ their TECH 2 while driving and see what it says.

The PCS (pressure control selonoid) is also a very common problem w/ GPs

Try www.clubgp.com see what some others might think.

Hope this helps alittle.


I posted on clubgp also, and they say TC or TCC solenoid also, what is the TCC solenoid and where is it?

Where if you are able to fix the problem then just replace it. After that make money to install an oil cooler. Heat is the worst tranny enemy

I posted on clubgp also, and they say TC or TCC solenoid also, what is the TCC solenoid and where is it?


After some thought I think it is the tcc solenoid. About 5,ooo miles ago I changed trans oil and filter, thought about it and there was no abnormal metal in pan and fluid looked great. If tc was going I think there would be metal in pan, plus it has been doing this for about 1.5 years so I think to tc would have gone byebye by now.

Anyone know how to replace the tcc solenoid?

Well if the Torque Converter Clutch is gone(all the way) would be either applied all the time or not engaging at all. The TCC is not that expensive, but, to replace it you have to take out the tranny cover that is under the airbox on the driver side to release it.
I believe also that the TCC would generate a SES if it was gone, get your car scanned to make sure there are no tranny related SES.
Let me tell you my tranny has only 3 months, it is Goodwrench reman and slipped when trying to accelerate, the damn thing temp was way passed 230 degf. I have been told that the tranny oil looses it's ability to lube the tranny after 240degf and you know that dry trannies sometimes shift hard, do not shift at all or slips.
So before you start taking your tranny cover out, There is an easy test you can do to check it, just take out the airbox. You would see on the tranny a round connector that has more than 4 cables. That is the TCC, just disconnect it and drive the car for a week or 2. If it stops then definetly is the TCC if not then check the Trouble Codes to see if there is anything related to the tranny. When you disconnect the TCC the car would have a little poorer mileage but would run normally. Go ahead and try it

Well if the Torque Converter Clutch is gone(all the way) would be either applied all the time or not engaging at all. The TCC is not that expensive, but, to replace it you have to take out the tranny cover that is under the airbox on the driver side to release it.
I believe also that the TCC would generate a SES if it was gone, get your car scanned to make sure there are no tranny related SES.
Let me tell you my tranny has only 3 months, it is Goodwrench reman and slipped when trying to accelerate, the damn thing temp was way passed 230 degf. I have been told that the tranny oil looses it's ability to lube the tranny after 240degf and you know that dry trannies sometimes shift hard, do not shift at all or slips.
So before you start taking your tranny cover out, There is an easy test you can do to check it, just take out the airbox. You would see on the tranny a round connector that has more than 4 cables. That is the TCC, just disconnect it and drive the car for a week or 2. If it stops then definetly is the TCC if not then check the Trouble Codes to see if there is anything related to the tranny. When you disconnect the TCC the car would have a little poorer mileage but would run normally. Go ahead and try it


I dont think its the clutch itself, I think it is the solenoid. Again I think if the clutch or the tc itself were going, there wouldve been metal in the pan when I changed it, this has been going on for over a year, I think either of those wouldve gone totally by now


How can I tell if the solenoid is bad?

If there is a solenoid gone north on the tranny you should have a SES light on or TC's on your car memory. Get the car scanned to check the codes if there are any. Again, real quick and cheap disconnect the TCC and check how the car behaves on the road.

jyount, dealer changed the solenoid...didnt fix the problem.(437 bucks) had to take it back. im pissed

and btw, i didnt have an ses light when the solenoid was bad. i would think that you need it pluged in for it to even shift.

It should shift, this controls convertor lockup, like he says, should change mileage, and maybe throw a code, but would run the same I think. Only problem, I don't know where it is, mine isn't under the airbox, only connector I see under there is on the a/c line.

the solenoid is inside the tranny. have to drain the fluid and tear into it.. not real major tho.
and um, i had to get a new transmission. they said my valve body and other things were messed up. it costed me $2400 with a 3 yr warrantee. the damn bastards for some reason didnt fill up the fluid. it was acting up on my way home. i wound up adding 4 F'ing quarts. fixed the problem tho. tranny feels strong...heck, i feels more powerful than it did before.. i could tell that the old one was wearing out.
jyount, hopefully you wont have to get a new tranny like me

"When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up.

The first trip they put the updated valve body in it and the problem still exists."

My car was doin the same thing and when i took it up to the dealer, they said that the Torque Converter Clutch was messed up, and they were gonna fix that and replace the valve body. We'll see how it goes when i get the car back tomorrow...

Tranny Go Boom... 2 and 4th gears are gone on mine. I guess Im going to have to have it rebuilt

that sucks. too bad it's so expensive to fix

"When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up.

The first trip they put the updated valve body in it and the problem still exists."

My car was doin the same thing and when i took it up to the dealer, they said that the Torque Converter Clutch was messed up, and they were gonna fix that and replace the valve body. We'll see how it goes when i get the car back tomorrow...


So did you ever find out why it was slipping? I think your the guy that was asking me about the same problem as me, and wondering about it in another post. My car is still slipping, Im going to be selling it soon... I just want to know what the problem was or is.

"When driving, usually when pulling a very slight grade and not in the gas too much the trans feels like its slipping, but it doesn't just slip, the tach jumps up and down and the car does some herky jerkin, no perticular speed does it any worse than another. Let out of the gas and it quits or floor it and it quits. Drive a little farther and it will do it again. This doesn't always happen, as the dealer has drove it about 150 miles between 3 trips to the shop and never had it mess up.

The first trip they put the updated valve body in it and the problem still exists."

My car was doin the same thing and when i took it up to the dealer, they said that the Torque Converter Clutch was messed up, and they were gonna fix that and replace the valve body. We'll see how it goes when i get the car back tomorrow...


So did you ever find out why it was slipping? I think your the guy that was asking me about the same problem as me, and wondering about it in another post. My car is still slipping, Im going to be selling it soon... I just want to know what the problem was or is.

"So did you ever find out why it was slipping? I think your the guy that was asking me about the same problem as me, and wondering about it in another post. My car is still slipping, Im going to be selling it soon... I just want to know what the problem was or is."

The mechanic replaced the whole valve body assembly, and that seems to have fixed the problem. The car is now shifting beautifully.

humm... how much did that run ya for?

my valve body needed to be replaced in my old tranny..was gonna be $1300(dealer)

I was still under the dealer's 60 day warrenty so it didnt cost me a penny. But it was an all day job, and the mechanic said that it would have been expensive... buy he didnt specify exactly how much it would have cost.

yup pc solenoid
cause pressure to fail