I was trying to fix this issue for my MIL. It's a 2004 LeSabre with 93k/mi. It started to have a 1-2 long shift, it wasn't slippage, seemed more electronic or something to me, upon acceleration it would shift out of 1st and rpm's would jump until you took your foot off the gas , and within 2-4seconds it would shift into 2nd. Definitely does not seem like slipping. She drove it for a week avg. 100mi/day and no smells, fluid was not burnt one bit, and most of all, during the delay, no forward drive movement at all, none, it's out of 1st and not in 2nd. It would do this generally only when warmed up, never when it was still cold.
While it didn't pop a light, it did have a code, the 1-2 long shift detected, in which case, it bumps the line pressure in an attempt to force it to shift (or so I read). In researching it seems it was fairly common issue, the pressure solenoid inside the side cover. Lots of different research resources pointed to that. WHile alot of work to get at, it's not expensive. She took it to a shop before I looked at it, they wanted to put in a whole new transmission for $3200.
So I did that, along with all the other solenoids behind that cover while I was in there, the 1-2 shift, 3-4 shift and tcc solenoids.
Giant can of worms to do that job, forgot to remove a brake line while dropping the cradle enough to get that side cover off, and it broke, because it was rusted so bad. A good line would have just broke the plastic clip. So I replaced all the brake lines with a SS set, since the lines had many other badly rusted spots, GM should be sued for these, forget 20lbs of shit on your keys and having to hit the keychain while panicking and running off the road and hitting something hard enough to pop an air bag, I've replaced countless GM vehicles rusty brake lines from 1965 to 2011's, friggen criminal they used plain steel up til 2014. The stabilizer links also busted from rust, of course.
Anyway, got it all put back together, also drained the fluid and put new filter and synthetic fluid back in.
Well, it still did it. Although not nearly as often as it was doing it. Before after it warmed up it would do it pretty much every acceleration from stop.Today it was only very occasionaly and less as time went by. So, now where do I go? Let it work in some more and it'll stop by itself? The accumulator piston? They make a shift kit with a new piston and spring that supposed to change or firm up the 1-2 shift. That's behind the pan, so pretty easy to get at unlike those solenoids. No idea what it is though, I would have bet a paycheck it was that pressure solenoid, the descriptions, codes and everything I found matched that problem. Seems, it wasn't it. But it really doesn't feel, sound or act like old transmission slipping.
Any ideas what it really could be? My only idea is to try that accumulator piston/spring thing. I don't work on automatics much. I've rebuilt several manuals, auto's...ehh....I prefer my manuals!
While it didn't pop a light, it did have a code, the 1-2 long shift detected, in which case, it bumps the line pressure in an attempt to force it to shift (or so I read). In researching it seems it was fairly common issue, the pressure solenoid inside the side cover. Lots of different research resources pointed to that. WHile alot of work to get at, it's not expensive. She took it to a shop before I looked at it, they wanted to put in a whole new transmission for $3200.
So I did that, along with all the other solenoids behind that cover while I was in there, the 1-2 shift, 3-4 shift and tcc solenoids.
Giant can of worms to do that job, forgot to remove a brake line while dropping the cradle enough to get that side cover off, and it broke, because it was rusted so bad. A good line would have just broke the plastic clip. So I replaced all the brake lines with a SS set, since the lines had many other badly rusted spots, GM should be sued for these, forget 20lbs of shit on your keys and having to hit the keychain while panicking and running off the road and hitting something hard enough to pop an air bag, I've replaced countless GM vehicles rusty brake lines from 1965 to 2011's, friggen criminal they used plain steel up til 2014. The stabilizer links also busted from rust, of course.
Anyway, got it all put back together, also drained the fluid and put new filter and synthetic fluid back in.
Well, it still did it. Although not nearly as often as it was doing it. Before after it warmed up it would do it pretty much every acceleration from stop.Today it was only very occasionaly and less as time went by. So, now where do I go? Let it work in some more and it'll stop by itself? The accumulator piston? They make a shift kit with a new piston and spring that supposed to change or firm up the 1-2 shift. That's behind the pan, so pretty easy to get at unlike those solenoids. No idea what it is though, I would have bet a paycheck it was that pressure solenoid, the descriptions, codes and everything I found matched that problem. Seems, it wasn't it. But it really doesn't feel, sound or act like old transmission slipping.
Any ideas what it really could be? My only idea is to try that accumulator piston/spring thing. I don't work on automatics much. I've rebuilt several manuals, auto's...ehh....I prefer my manuals!
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