Automatic transmission issue

[Guffman69]

Dr. I have a 91 240sx, with 210,000 miles on it, my auto transmission was rebiult for the first time at 194,000 miles. (live in MD). It seems like all the transmission issues that I had prior to the rebuild still occur, such as notchy starts on cold morning etc. One thing that has always been there is that occasionally the car does not want to go into overdrive. It will stay in gear no matter what the speed and when you let off the gas instead of having torque from the engine slow you down the revs just go down. This problem is intermittent and the transmission will work fine for months and all of the sudden will experience this thing happen...then as suddenly as it came it will go back to normal..sometimes while driving...it will just go into overdrive. Another related symptom is that the car does not seem to start in 1st gear...basically it seems like it goes from 2nd to third and just stays there. The problem also seems to have something to do with extreme temp changes, at one point we had steadywarm weather and suddenly got cold..that is when it stopped going into gear, after about a week of driving it started running normal again until last month when we hit a warm spell and it just didn't shift again. I only drove the car on the old transmission for a month before it went bad, and only experience one instance of it not shifting at that time (though that was in the fall with relatively steady temps). My brother owned the car prior to me and only stated he had issues with knotchiness on cold mornings until the transmission warmed up...any suggestions..The car has run flawlessly otherwise and though I am not prepared to replace another transmission, but I feel it is still in to good of shape to just give up on,Any help would be appreciatedTim

[SHIFT_Z]

I had a problem similar to that with my old car. Did your have your transmission rebuilt by transmission spealists or a dealer?

[Mayhem_J30]

with only 16,000 miles since the rebuild more then likely IF there was any warranty at all on the last job I imagine it's gone. Sounds like you're having a series of probs with the transmission though. TC not locking up and it's going into safe mode...3rd gear permanantly. Your rebuilder either did a shotty job or something else is at play. Have you checked your fluid level? When you say 'knotchiness' do you mean rough shifting? is so, that's normal until fluid is warmed up. You can try a good ATF to help that problem, like Mobil 1

[Guffman69]

The knotchiness is only in first gear and related to the engine/transmission being cold, so I think your right it is a fluid problem, level is fine. But the "safe" mode sounds interesting, only I definately have two gears, feels like second and third but won't shift over to overdrive..I don't think 1st is there either...guess I will have to take it in thanks

[1989240MAN]

i am having the EXACT same problem you are having. it startedabout 2 weeks ago. please inform me of your results

[drjohn]

It sounds like a internal pressure leak past a lathe seal or a clutch pack. The trans shop should be able to find it with a pressure check. If it is a electical problem the a/t light will flash with a code, if not it's a hyd. leak internally. In fail safe the trans locks in 2nd or 3rd gear and won't go over 2500 rpm if memory serves me right !!!!