Basically what the title says, I lost first gear and I lost O/D, 4th gear. This is a 4L60E transmission out of a 95 Camaro Z28. I got the trans rebuilt last March due to the 3/4 clutches burning out. I have maybe 6xxx miles on it since the rebuild.

Here is exactly what happened when I lost 1/4th gears: I took my car to the track on Saturday, the 17th. I had just got a tune done so I was wanting to see what gains I made. I pulled up and did my burnout; 1st, 2nd, 3rd then rollout. I staged and put my car in Drive. I stalled it to around 2000 rpms and launched and it wheel hopped a little so I let out of it for a split second and got back into it and it immediately shifted into second the straight to third; or it might have shifted straight to third, I'm not sure cuz it happened real quick. (At this point, I didn't know first was gone) I pulled back around and let my car cool off for a few then went to make another run so I went to do the burnout and it was real sluggish so I pulled up to stage and launched and it was terrible so I just cruised down the track. When I got back to the pits I checked my trans fluid and it was fine. Then I started doing research on google and came to the conclusion that it was the 1-2 shift solenoid. The next day I went and bought one and put it in my car. Still don't have 1st gear or overdrive.

The symptoms I am having match the description that it would be a solenoid. It shifts harder into gear now then before. And I only have second gear if I put it into "2" or "1". If it's in "D" or "O/D" then it goes straight to third gear. I also have reverse.

Here's what I have tried so far:
-Replaced shift solenoid.
-Grounded the wire to the 1-2 shift solenoid, and still didn't have first.
-Checked fuses in both spots and all was good.
-Checked the 12V wire that runs to the trans and I'm getting power to the transmission.

I also tried to scan for codes on the transmission on 2 different scanners and neither will connect. One just said "error" and the other one said "Connection Lost"

Any feedback/advice/tips etc would be greatly appreciated!

 

Starting in 3rd generally indicates limp mode and a code scan will tell you the reason. In limp mode both solenoids are off. Forcing ON the 1-2 shift solenoid (also called Solenoid A) will put the trans into 4th gear when solenoid B is OFF.

I think you need to find the reason you cannot scan for codes. Solving that may solve your trans problem or at least give you a reason.
So for I don't think there is anything wrong with your trans, sounds like an electrical or PCM problem.

 

I was leaning toward the problem being the PCM. Anyway to tell if that is the problem? Other than swapping it with another one??