So im looking to replace my transmission shift linkage, whatever that is. Can somebody please do the following:

1. Tell me what this is and what it controls.
2. Tell me its official name so i can look it up at autozone.
3. Tell me the symptoms of a bad cable and what happends when it starts getting bound up (which is what my friend said it was doing in the past).

I would greatly appreciate it! Tyvm

This is for a: 1990 Pontaic Firebird 3.1L V6

 

Which trans cable are you referring to ?
Shift linkage would be what goes between shifter and trans ; you use to select the gears ;P/N/ D

Throttle valve cable (TV cable ) goes between the engine and trans and is what controls the gear shifts.

 

Ya the first one. I already know of the TV cable and am going to replace that since it doesnt seem to be working correctly with a newly rebuilt transmission. However in the past my friend was saying the "Linkage" was getting bound up and so im wondering whats the effects of a "bound" or "bad" linkage. I know of 1 problem i have right now which is i cant manualy shift into 1st gear, its like jammed. This is an automatic transmission so just putting it in Drive is fine, and 1st gear works flawlessly, and its a new rebuilt trans so im 100% positive its not a transmission problem, so im trying to figure out why i cant manualy goto 1st gear. 2nd and up works just fine.

 

Maybe the shift cable just needs adjustment where it bolts to the tranny shift arm. The arm has a slotted hole iirc which allows for a bit of adjustment. You'll need to do this adjustment anyway if you buy a new shift cable, so might as well try on your current one. If it's not damaged, you should be able to get it to a position where it goes into both 1st and park ok (opposite ends of travel).

You might have some difficulty finding a new shift cable, GM has discontinued them. There are a couple of aftermarket ones, but have a bad rep for breaking easily. The consensus seems to be get a good OEM one from a jy if you can.

 

Thank you, this has given me enough info to find the cable i needed on ebay for around $30.00

 

Do it soon ( like before you drive the car again
a non working or incorrectly adjusted TV cable can make your nice new trans burn up real fast

 

see thats what i keep telling my dad since he's the one using the car to goto work and back every day! But he wont believe me, he wants to believe the mechanic that told him it wont hurt it.

Basicly the trans doesnt shift correctly when you punch it, it just bogs down on gas and switches when it feels like it. Its a bad TV cable im sure since its doing exactly what my last transmission did before it got so much worse which is why i had to replace the tranny. So now im positive its a bad TV cable.

Luckily my dad only drives it in town and goes easy cause going on longer trips or highway is when it can get bad since its not changing correctly.

 

Just want to second what vette said and make you fix this asap, before you damage it, if it's not already. Tell dad to stop driving it RIGHT NOW, until you make the adjustment. Which takes a couple minutes if the tv cables is ok.

This is way more important than the shifter cable. Also get a new mechanic.

Here is a site thats usually used as a reference around here:

http://www.tvmadeez.com/

Read the TV101 section. It's long, wordy, and informative.

 

I wish it were that simple. My dad paid for the new rebuilt transmission and i told him multiple times he's going to ruin it just like how the old one went out. He doesnt want to believe me so when i get the new cable next month and have it installed, if its already ruined, i simply wont pay him back for the 500 bucks he spent plus the 200 to have it put back in the car. Seeing as how i would have to pay that money out to have it done AGAIN. So thanks everyone for the great info and i only hope next month when the cables put in, its not too late.

He only drives it in town and goes very easy on it and probly never exceeds 40 mph. Could this still mess it up?

 

YES..

The Throttle Valve cable is the most important cable on the transmission.. When adjusted properly it will allow the transmission to shift properly, If not adjusted right it will help destroy a transmission. Another user already posted the link to help adjust it.. Follow it.. Only takes a few seconds.. You won't regret it afterwards if it is adjusted right..

 

The various clutches, and band, requires adequate hydraulic line pressure to keep them engaged. The pressure required to do this increases with rpm amd load, thus the tv valve is used to provide this regulation. More throttle = higher pressure - firmer engagement.

If the tv valve is not producing adequate line pressure, clutches and band will slip continuously, and burn out. Just like you can burn the clutch out in a manual, by dumping it on too many burnouts.

If you have the situation where it's upshifting too early, and the shifts are sloppy, it won't last long. Not even doodling around town. What's the arguement? It's an almost idiotically simple quick adjustment, and will save tons of cash. Go do it yourself. In fact, it's something the mechanic who replaced the tranny should have done at the time.

 

Very good information.

 

Its not shifting early or late, its shifting fine. However it simply wont kick down if you try to floor it to pass somebody up, it just eats gas and changes gears at the same time it would had you been just crusing around, so around 2-3k rpm i think. I sappose this means its still not too late to fix the issue. Unfortunately as i said, my dad isnt going to stop driving it to work and back even if i tell him he's going to ruin that transmission as everybody on here couldnt be wrong.

I will try searing it into his old brain and make him believe that if he doesnt go and get a new TV cable and have it installed or bring it to me so i can install it, then im not going to pay him back for the $700 he has invested in it.

 

found out today that he's only driving it about once a week cause it has no insurance on it haha. once a week is definately better then every day.

 

The TV cable has been ordered and is on its way. Should be here as soon as tomorrow (Tuesday) or next week on Monday. Time to read up on the TV cable 101 so i can install it when it gets here.

 

Ok! I have fully read the tv cable 101 and think i fully understand how to set it up. So correct me if im wrong, but heres what ill do right?

1. Install the end of tv cable into transmission where that little hook is, and screw it in (the 6mm bolt).
2. Connect the front of the cable up the top of engine where it latches in.
3. Connect the eyedrop plastic piece to the throttle area.
4. Press the "D" looking button and push the cable in towards the transmission as much as possible until it no longer goes in anymore.
5. Release "D" button, go inside the car and push petal to fully open.

Then thats it? Of course before i connect it im going to test to be sure the pedal fully open and another person at the engine isnt able to open it further, which would mean i need to fix that before anything.

 

Yep, thats it.

 

Awesome, then ill do so on saterday when the cable arrives. Thank you everyone for all the great info and tips, i now know even more about the car i love most.

 

Just a word of caution, the aftermarket cables are very fragile at the bottom where the plastic sleeve goes around the cable where it attaches to the transmission. I broke the aftermarket one trying to install it in a hurry. The factory one is discontinued but I was able to source one at the Chevrolet dealership in Guam and ordered it. There may be one more as they said they thought there was one extra. You will pay a lot but you get what you pay for.

 

I see, i will be very carefull with that part. Thank you very much for the info

 

Pretty much. I just hold the button in, push the cable towards the windshield. Let go of the button.... Instead of pushing the gas pedal, just turn the throttle bracket where the cable is hooked on. Rotate the bracket to WOT. You'll hear it ratchet into place. Let go of the throttle bracket and you're done.

 

Ok everything has been installed and i took it on a couple test runs. Something still seems a bit off. Its kicking down fine when i floor it and stays in lower gear when flooring it till around 4k rpm then switches. Driving normaly/easily and it switches around 2k rpm up till overdrive. Does this sound about right?

Also i noticed that when i set the TV cable, it didnt click at all when my friend pushed the petal all the way down, it just pulled the cable out and back in when he got off throttle. Seems like it didnt set anything. Also when he took the old tv cable out, is the little hook sapposed to retract back into the transmission or just hang there where you can very easily grab it with fingers and hook it onto the new tv cable?

Cause it didnt retract back into the transmission at all, so could this mean the valve body was never rebuilt and is wore out hence why its not retracting the hook? This trans that i got was a rebuilt trans for $450 and i gave them my old one.