Headers installed, now trans issue? [Archive] - GrandAmGT.com Forum

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Brken123
06-14-2007, 08:57 AM
Ok I need some help here. Recently I had a set of S&S headers put on the car. During the install, the battery was unhooked. Now I know when you unhook the battery, the car has to "relearn" the shift points when it comes to the transmission.

My question : It's been almost 3 weeks now, and I drive the car every day 25 miles each way to and from work. When shifting between gears, the shifts are fine. However, when the car is in second gear, interesting stuff happens. If it's second gear around 2500 RPMs, and you give it a lot of gas (but not enough to make it downshift back to first) it starts to accelerate, and then seems like it jumps out of gear, revs up, and then kicks back into gear. This "hiccup" will happen 3 to 4 times before it shifts into 3rd gear.

Could this be releated to the battery being unhooked and the relearn process occuring? I would think after 3 weeks that it would be pretty much set - or am I totally wrong?
I'm not getting any SES lights or anything like that. Transmission fluid has never been flushed, as I bought the car with 30,000 miles on it and my mechanic told me if the trans hasn't been flushed religiously every 10,000 miles, not to do it at all as it can cause it to wear out even faster due to removing the gum and gunk that's holding it together. Now the car has 95,000 miles on it. I haven't abused it (such as burnouts, neutral drops, etc).

I'm wondering if it could be the trans is starting to go, or if it's something simpler then that - can anyone offer suggestions as to how to go about figuring out what's wrong?

Any/all help is appreciated. Thanks!

ledfreak
06-14-2007, 11:19 AM
Transmission fluid has never been flushed, as I bought the car with 30,000 miles on it and my mechanic told me if the trans hasn't been flushed religiously every 10,000 miles, not to do it at all as it can cause it to wear out even faster due to removing the gum and gunk that's holding it together. Now the car has 95,000 miles on it. I haven't abused it (such as burnouts, neutral drops, etc).

I'm wondering if it could be the trans is starting to go, or if it's something simpler then that - can anyone offer suggestions as to how to go about figuring out what's wrong?

Any/all help is appreciated. Thanks!

If your trans fluid & filter have never been changed since you've had the car it would be a good idea since GM recommends it be changed every 50k; you're overdue. This may or may not have some thing to do with your "odd" shift.
As far as your mechanics "10,000" statement goes; I personally wouldn't recommend flushing the GA trans every 10k (more chances to introduce foreign matter, air, etc.).

Just change the filter & fluid for starters, NOT a flush. You also might want to check the wiring to the trans switch & your battery cables too.

AaronGAGT
06-14-2007, 11:44 AM
sounds almost like a misfire

Brken123
06-14-2007, 04:58 PM
Ok so I've done some playing with it, and the problem is only once it's in second gear. I drive 2 main highways here to get home from work (for those familiar with PA I run I476 and I 95 every day). I noticed if I let it drop all the way to first gear, and then get on it (not floor it, but moderate acceleration) it will go through first no problem, shift to second, and then get to about 3000 rpms, slip, catch, run up to 4500, slip again, catch, and then wind out the gear, then shift to third and be smooth the rest of the way up to whatever speed.

Then I got moving at about 45 MPH or so, and had it in 3 instead of D to disengage the TC lockup, and got in it enough to cause it to downshift. It downshifted fine, and then once in second it slipped or surged or whatever you want to call it around 3500 rpms, and again at 4500 rpms, then went back into third, and was fine all the way back up to speed.

Once I got home, I went to a flat, level backroad, and came to a stop. I shifted it all the way down to 2, and then gave it moderate gas again. It went all the way through first, into second, and all the way up to 5 thousand rpms with no slipping at all. I drove it all the way home in second from this backroad (about 2 miles or so) in 2, and kept it around 35 mph, and it shifted fine with no slippage. I'd also wait until just after it shifted into second and then hammer it, and even then it didn't slip.

So based on the above, I'm thinking it's computer related, being that the shift points and line pressure are computer controlled, but what is throwing me is why it slips in second gear, and only second gear, when the shifter is in 3 or D, but doesn't slip when it's in 2. I may be taking it to AAMCO over the weekend to have them diagnose it, but before they fill my head with crazy ideas of what it might be, can anyone offer some suggestions/advice?

XtremeGaGt00
06-14-2007, 05:02 PM
ive got the same exact problem...i have no clue what it is!?!?

gectek
06-14-2007, 10:13 PM
trans is going x2

Brken123
06-15-2007, 10:52 AM
trans is going x2


What do you mean trans is going? I'm thing maybe a silenoid or possibly a "band" is bad, but doubting the whole trans is shot. If it is, I'll be really pissed considering I just put a bunch of money into this car that would have been a nice down payment on a newer vehicle. I'm going to have it looked at this weekend, and I'll see what the diagnosis is. If it is indeed shot, it'll be going as a trade in for sure!

gectek
06-15-2007, 03:56 PM
yah i think the trans is going, either slipping clutches, usually not a solenoid issue, those would go while the gear is engaged and slip up and down by a few thousand RPM, a few hundred could be the converter clutch, but not like that because the gear u said doesnt engage. it could be the band though...umm im thinking the 2-4 band, that one is at least a little close to the outside, and u can check the engagement by taking out the 2-4 servo off the bottom and pushing on it with a screwdriver to make sure it is ok...and also check for scoring on the drum, u can see it a little bit just use a good light, also look for big chunks in the fluid and metal parts on the magnet or in the pan

Sprucegagt
06-16-2007, 11:30 PM
Ok I need some help here. Recently I had a set of S&S headers put on the car. During the install, the battery was unhooked. Now I know when you unhook the battery, the car has to "relearn" the shift points when it comes to the transmission.

My question : It's been almost 3 weeks now, and I drive the car every day 25 miles each way to and from work. When shifting between gears, the shifts are fine. However, when the car is in second gear, interesting stuff happens. If it's second gear around 2500 RPMs, and you give it a lot of gas (but not enough to make it downshift back to first) it starts to accelerate, and then seems like it jumps out of gear, revs up, and then kicks back into gear. This "hiccup" will happen 3 to 4 times before it shifts into 3rd gear.

Could this be releated to the battery being unhooked and the relearn process occuring? I would think after 3 weeks that it would be pretty much set - or am I totally wrong?
I'm not getting any SES lights or anything like that. Transmission fluid has never been flushed, as I bought the car with 30,000 miles on it and my mechanic told me if the trans hasn't been flushed religiously every 10,000 miles, not to do it at all as it can cause it to wear out even faster due to removing the gum and gunk that's holding it together. Now the car has 95,000 miles on it. I haven't abused it (such as burnouts, neutral drops, etc).

I'm wondering if it could be the trans is starting to go, or if it's something simpler then that - can anyone offer suggestions as to how to go about figuring out what's wrong?

Any/all help is appreciated. Thanks!

You may have the same problem as me, pressure control solenoid. But is yours temperature related? Meaning my car will slip just once in 2nd gear at around 2500 rpm, but only after the trans fluid is above 140*F. If your car is slipping no matter what the trans temperature is then gectek may be right.

Brken123
06-17-2007, 11:22 AM
You may have the same problem as me, pressure control solenoid. But is yours temperature related? Meaning my car will slip just once in 2nd gear at around 2500 rpm, but only after the trans fluid is above 140*F. If your car is slipping no matter what the trans temperature is then gectek may be right.

It only does it once it warms up. Is a pressure control solenoid hard to replace?

Sprucegagt
06-17-2007, 06:42 PM
You'll have to drop the transmission in order to change it. It's located behind the side pan in the valve body. Do a search on pressure control solenoid and look for a thread started by blackrider. He took pictures showing what was needed to change his.