1982 auto transmission won't shift
12-01-2020, 10:39 AM
#1
Instructor
Thread Starter
1982 auto transmission won't shift
Hi all,
2 weeks ago I have purchased my first C3 collector edition.
My expertise is more in German cars, but always wanted C3.
So, the lady I bought the car from (Orlando,FL)rebuilt the transmission last month. At the same time the ECM died and she give up on counting fixing the car. I have replaced the ECM and the car start immediately but won't shift into drive.
I don't know much about this GM transmission but I would like to troubleshoot this issue before I have to tow the car 300 miles for warranty services.
is it elctronic? Or cable? Internal solenoids? Vacuum valves?
Please advise.
Dan.
2 weeks ago I have purchased my first C3 collector edition.
My expertise is more in German cars, but always wanted C3.
So, the lady I bought the car from (Orlando,FL)rebuilt the transmission last month. At the same time the ECM died and she give up on counting fixing the car. I have replaced the ECM and the car start immediately but won't shift into drive.
I don't know much about this GM transmission but I would like to troubleshoot this issue before I have to tow the car 300 miles for warranty services.
is it elctronic? Or cable? Internal solenoids? Vacuum valves?
Please advise.
Dan.
12-01-2020, 10:56 AM
#2
Le Mans Master
Will it shift to reverse? If stuck in park, Check the switch on your brake pedal and the wiring associated with the solenoid.
Last edited by Cooter Tech; 12-01-2020 at 10:59 AM.
12-01-2020, 11:18 AM
#3
there is nothing Electronic inside the transmission that would keep it from moving forward ..... Does the shifter not shift into Drive **or** the shifter shifts into drive and vehicle does not move ?
12-01-2020, 02:09 PM
#4
Instructor
Thread Starter
12-01-2020, 02:10 PM
#5
Instructor
Thread Starter
Last edited by Idan55; 12-01-2020 at 02:18 PM.
12-01-2020, 02:25 PM
#6
Le Mans Master
1982 all Automatic trans corvettes had a 700-R4, 4 speed trans. That trans has a cable that controls the shift points, along with how firm the shifts are. The only electronics in that are controlled by the ECM and that is limited to the engagement of the torque converter clutch. If it's not moving, or even trying to move when the selector is placed in R or any of the drive positions, I'd check the cable from the shifter in the car and the attachment to the trans. The nut that holds the lever on the trans has been known to get loose and allow the lever to disengage from the shaft. Also check the fluid level- if it's low, the pump can't build enough pressure to make the clutches engage. Past all of that, and still no resolution, it's time to drop the pan and have a look. If the fluid on the dipstick now smells bad or is really discolored, it's probably time for a trans rebuild.
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RLI (12-04-2020)
12-01-2020, 02:51 PM
#7
Instructor
Thread Starter
1982 all Automatic trans corvettes had a 700-R4, 4 speed trans. That trans has a cable that controls the shift points, along with how firm the shifts are. The only electronics in that are controlled by the ECM and that is limited to the engagement of the torque converter clutch. If it's not moving, or even trying to move when the selector is placed in R or any of the drive positions, I'd check the cable from the shifter in the car and the attachment to the trans. The nut that holds the lever on the trans has been known to get loose and allow the lever to disengage from the shaft. Also check the fluid level- if it's low, the pump can't build enough pressure to make the clutches engage. Past all of that, and still no resolution, it's time to drop the pan and have a look. If the fluid on the dipstick now smells bad or is really discolored, it's probably time for a trans rebuild.
I will check the cable and oil level tonight.
Transmission was rebuilt last month and yesterday was the first time the car started (waiting long time to replacement ECM and PROM). This is why I belive the mechanic has forgotten to connect somthing.
12-01-2020, 04:10 PM
#8
Team Owner
Proper setting of the T.V. (throttle valve) cable is essential for long life of the transmission. If inadequate T.V. pressure is produced when at WOT, clutches will FRY!! 
12-02-2020, 01:12 AM
#9
Instructor
Thread Starter
How do you do proper settings for the cable (throttle valve)?
I don't see any regulation nut connected into the transmission, is it from the shifter?
Also, do I check the transmission fluid when motor is running and shifter at P?
I don't see any regulation nut connected into the transmission, is it from the shifter?
Also, do I check the transmission fluid when motor is running and shifter at P?
12-02-2020, 12:16 PM
#10
Instructor
Thread Starter
12-02-2020, 08:20 PM
#11
Instructor
Thread Starter
Ok, I have checked today the transmission cable. From the shifter to the transmission, all looks good. The cable work as expected.
Transmission fluid is new. Fluid level are as required.
I still can't find the T.V cable.
might have to take the car back to the shop
Transmission fluid is new. Fluid level are as required.
I still can't find the T.V cable.
might have to take the car back to the shop
12-03-2020, 12:20 AM
#12
Team Owner
Specifically, that cable needs to be adjusted by monitoring the hydraulic pressure from the T.V. pressure tap on the left side of the transmission...while the engine is running and the throttle cable and T.V. cables are disconnected from the carburetor linkage. The linkage and T.V. connection point on it need to be set up so that at 'closed throttle' position, T.V. pressure is at minimum...AND....so that at WOT, T.V. pressure is maximized WITHOUT PUTTING THE TV CABLE IN A BIND (you can not go completely to full travel of the cable when at WOT)
If you do not have a carb with linkage specifically designed to accept the T.V. cable & transmission that you have joined with it, this effort is a puzzle of geometry and where to locate the cable connection point so that the two requirement listed above are met satisfactorily. Do this sound a bit complex? Well, it can be if you don't do this stuff on a regular basis. And most of us don't.
I'm only going into detail on this because I don't want to see a post from you next week that your work just went up in tranny smoke along with some of the internal clutches. I want you to be successful & I need to make you aware of the importance of getting this cable set PROPERLY. You best guidance is to do some research on the web about this issue and learn the important aspects of it, so that you can do the job well or so that you can find someone (or a shop) that can set it up properly for you.
Wish you luck!!
If you do not have a carb with linkage specifically designed to accept the T.V. cable & transmission that you have joined with it, this effort is a puzzle of geometry and where to locate the cable connection point so that the two requirement listed above are met satisfactorily. Do this sound a bit complex? Well, it can be if you don't do this stuff on a regular basis. And most of us don't.
I'm only going into detail on this because I don't want to see a post from you next week that your work just went up in tranny smoke along with some of the internal clutches. I want you to be successful & I need to make you aware of the importance of getting this cable set PROPERLY. You best guidance is to do some research on the web about this issue and learn the important aspects of it, so that you can do the job well or so that you can find someone (or a shop) that can set it up properly for you.
Wish you luck!!
12-03-2020, 01:26 AM
#13
Melting Slicks
Are you in the USA? If not, can you provide what country you are in? The first thing you NEED to do is buy a GM 1982 service manual. It has all the information you need to set the TV cable correctly and maintain/troubleshoot the 82 CFI. Like mentioned, if you get the TV cable setting wrong, it will NOT take long before you WILL burn up the trans. The TV cable adjustment is at the TB linkage under the hood. It is a press button"click ratchet" arrangement. It doesn't take a lot to set it up, but it is specific. PLEASE buy a manual and save yourself tons of time playing a guessing game.
12-03-2020, 06:50 AM
#14
Team Owner
Actually, the service manual does not have ALL the information on how to set up a T.V. cable system when installing it on carb linkage which was NOT made to accept it.
It shows how to set the 'closed throttle' position with the cable; but the "difficult" stuff is not included since the cable, trans, and carb are already made to work properly when assembled.
For folks 'marrying' these pieces when they are NOT designed to match as a set, you have to 'grind it out' the old-fashioned way: figure out how it needs to work, then "make it so".
It shows how to set the 'closed throttle' position with the cable; but the "difficult" stuff is not included since the cable, trans, and carb are already made to work properly when assembled.
For folks 'marrying' these pieces when they are NOT designed to match as a set, you have to 'grind it out' the old-fashioned way: figure out how it needs to work, then "make it so".
12-03-2020, 07:50 AM
#15
Melting Slicks
Actually, the service manual does not have ALL the information on how to set up a T.V. cable system when installing it on carb linkage which was NOT made to accept it.
It shows how to set the 'closed throttle' position with the cable; but the "difficult" stuff is not included since the cable, trans, and carb are already made to work properly when assembled.
For folks 'marrying' these pieces when they are NOT designed to match as a set, you have to 'grind it out' the old-fashioned way: figure out how it needs to work, then "make it so".
It shows how to set the 'closed throttle' position with the cable; but the "difficult" stuff is not included since the cable, trans, and carb are already made to work properly when assembled.
For folks 'marrying' these pieces when they are NOT designed to match as a set, you have to 'grind it out' the old-fashioned way: figure out how it needs to work, then "make it so".
12-03-2020, 09:41 AM
#16
Melting Slicks
The procedure is simple and quick to do.( with motor off)
1. depress the "ratcheting" button on the TV cable module attached to the intake.
2. manually pull the the throttle forward to WOT while continuing to depress the button.
3. when at WOT, let go of the button to set the kickdown range
I've done it this way a couple times
FAST
1. depress the "ratcheting" button on the TV cable module attached to the intake.
2. manually pull the the throttle forward to WOT while continuing to depress the button.
3. when at WOT, let go of the button to set the kickdown range
I've done it this way a couple times
FAST
12-03-2020, 10:13 AM
#18
Instructor
Thread Starter
I live in south Florida.
How many cables are connected into the transmission?
I thought only 1, shifter to transmission.
I also thought the T.V cable is connected to the gas paddle.
I'm kinda lost over here. I don't have a problem with acceleration.
How many cables are connected into the transmission?
I thought only 1, shifter to transmission.
I also thought the T.V cable is connected to the gas paddle.
I'm kinda lost over here. I don't have a problem with acceleration.
Last edited by Idan55; 12-03-2020 at 10:14 AM.
12-03-2020, 12:50 PM
#19
TV cable adjustment is not the reason it won't move , but IF the TV cable is not adjusted right it will either cause hard late shift or super soft shifts that can burn up a transmission clutches and Band
12-03-2020, 01:13 PM
#20
Instructor
Thread Starter
You can shift to Park and run the motor, but have to the TV connected properly to create oil pressure.
I find his vedio very helpful and will test it tonight: