Car dies in reverse.

[w1kk3d]

I had my trans rebuilt last February due to failed 3rd/4th gear... it was a "custom rebuild" at a local shop. Also rebuilt the torque converter, and cleaned/flushed out the trans cooler.

Fast forward ~7months.
I let the car warm up at least 5mins, even in summer.
So, Septemberish rolls around, and I notice when I first shift it into drive after letting it warm up, and lightly feather the gas, it barely wants to move. If I give it heavier foot, it starts rolling fine.
If I put my beater Camry in drive, it starts rolling without me even giving it gas, like it should.

Same situation, if I put it in reverse, it insta-dies.
Once I restart it, I can put it in reverse again and it's fine.
After driving a while, no feathery 1st gear, no reverse issues.

I did a little searching, and I think maybe it's the line pressure? Not exactly sure.

I don't drive it now, and kept putting it on the back burner/forgetting about it, but I need to take it back to the shop and have them take a look at it under warranty before I run out of time.

Is it the shops fault for not diagnosing/fixing this previously? I don't think "custom rebuild" meant complete rebuild, and they didn't replace what was still 'working'.
The last thing I need is for them to say "sorry, not our fault" and me be stuck with a failing trans.

Thoughts? Suggestions?

 

[mrfister11]

old thread but torque converter bad.. if its locked or gets stuck it will die.. but usually it will do it in any gear.. unless you figured it out since then?

 

[w1kk3d]

I took it back to the shop that rebuilt it all, and they did say the torque converter was bad.

Also, they said there was surface rust on all the steel parts inside the trans. I'm not sure how that happened?