PoorMan

I first noticed my car was not shifting into 4th the other day at any RPM. In fact, I cann't even tell it's shifting from 1st though 3rd with the selector in OD. I mean; the RPM do not drop at all between those gears. It feels like it may be stuck 3rd all the time when the selector is in OD. The car has almost no pickup until 2k rpm.

I can shift it manually though and shift 1-2, 2-3, but not 3-4. These shifts fill very strong and crisp. Any suggestions on what it "can" be?. Trans has 73k miles and has very little hard use.

Thxs
JD

Smitty

Get a scanner on it and check the solenoids,also make sure p/n switch & the fluid pressure switch (verifys manual lever position by fluid pressure) are reporting the correct gear positions.

SMOKINV8

iTrader: (6)

I just got done fixing the a very very similar problem with mine.

https://ls1tech.com/forums/automatic-transmission/161121-intermittent-trans-problem-autotap-scan-included.html
https://ls1tech.com/forums/automatic-transmission/162895-write-ups-changing-solenoids.html

There is a single solenoid (mentioned in the second thread) which controls the transmission as far as shifting into 1st and 4th. Your OD (converter locking up) is probably working fine, but your car isn't shifting into 4th. To see if it's shifting into 1st (which I don't think it is, judging by your description), put the shifter into 1, then drive to a speed where your RPM's are at about 3k or so, then put it in 2 and see if you can feel it shift. If you don't, you probably started out in 2nd gear, so there was no first. Shift it into 3, and see if you feel it shift, I think you probably will. If you put it in OD, you'll feel the converter lock up if the trans is warm, if not, you probably won't feel anything. The only for sure way to tell if it's shifting into 4th or not is by scanning it.

Hope this helps.

PoorMan

Thanks for the suggestions. I will run a Datamaster log to see if the PCM is commanding the trans to shift to rule that out. The car came with a 2.73 rearend so I don't have the "1" on the gear selector. I need to remove that clip thingy under the console so I can try the manual 1-2 shift.

The solenoids don't sound like a super expensive item. Can you get them anywhere? like a autozone, etc. or is there a good online place that sells them.

Thanks
JD

PoorMan

I was also told today that if the solenoids do not get enough voltage they will be turned off/not work and the trans will "default" to stay in 3rd gear. Sounds weird but my battery has been reading low and in fact I had to have the car jumped the other day. Geez, butterfly effect I guess.

JD

PoorMan

I got to run DataMaster on it and I get a DTC 83 code. "TCC control feedback fault". The code is constantly being set from the moment I start the car. I guess it needs replaced? were it it located in the trans? back;front?
JD

Smitty

Some electrical faults within the TCC circuit will cause the PCM to inhibit 4th gear.Looks like it may be your TCC solenoid.Be sure to inspect the transmission internal harness for any spots that might have worn through from rubbing while the pan is off.With the transmission pan off,the TCC solenoid is located on the pass. side front between the pan rail and the vavle body.It has two 10mm headed bolts that hold it in,with one red and one balck wire going to it.

PoorMan

You will not believe this. After searching threads all day long I found one that said that the number codes mean different things year to year. A code 83 on my 94Z doesn't even have anything to do with the trans. On a 95 model a code 83 is the TCC fault code. That's strange. I thought all OBD1 computers are the same. Then I checked the bin file and it's for a 95 model car. I loaded up a 94 bin and the trans started working again with no codes.

Since my 94 model does not have the sensor that sets this code the 95 bin flashed on the computer thought it was broke and defaulted to a 3rd gear only "limp" mode.

JD

Smitty

Great!Glad to see things worked out for you.For a lot less money too.