cimchazz1

Ok, here we go again, another TV cable question.
I bot this car a few months ago and was told it needed a trans rebuild because it wouldn't shift out of 1st gear, (but I thought I felt it downshift to 1st once coming to a stop slowly when I test drove it). I changed the fluid, just had some thick black goo in the pan bottom and pink fluid. I readjusted the TV cable many times, and it shifted a few times, so I thought maybe it could be saved. It looked like the TV cable was newer than everything else under the hood, which all looks original (even the junk injectors are still there). But this cable also had the square button. You never know with a used car what the history is, could be a rebuilt or replaced with used trans, maybe somebody put a shift kit in, who knows?????? But what I discovered today, (and here comes the question), is that I finally got it to shift "normally" by adjusting the TV to wide open throttle, then pushing the square button in and backing the cable casing back out towards the firewall slightly. Now when I drive at a slow speed, it shifts at 2500 rpm, (and actually shifts pretty tight from 1st to 2nd), but I'm happy it's finally shifting. Does it sound like there is a cable issue, or TV issue, or what? I seems like if I set the cable to wide open throttle, I won't have enough pressure at normal driving speeds to shift the trans. Or is it a governor issue? Or is this something that can happen if someone put a TV spring in that is too long or too stiff, making the regular TV cable adjust process not work. I assume the pressure is too low if I adjust to WOT.
No telling who did what. The story was the guy was just driving along, came to a stop light, and it wouldn't shift again. Could be more like the guy put in a shift kit, changed the cable, took it for a drive and did a few hole shots (which pulled the cable all the way out), and it wouldn't shift again, who knows? What should my next step be, besides sell it?

65Z01

You could drop the A4 pan and see if the TV cable is too slack when adjusted per spec.
Also, a fluid pressure check seems in order as improper pressure can quickly ruin an A4.

coupeguy2001

Tell you what I'd do, I'd drive it the way you have it set up to shift, and every 50 miles for 2000 miles, I'd suck the trans fluid out of the dipstick tube and refill till it didn't change colors any more. beats jacking it up and changing fluid at home since you aren't going to drain the converter anyway.
I will bet the fluid is starting to soften whatever goo is in the trans passages, and your fluid will carry the contaminants out if you remove the contaminated fluid.
Then after a while, I would take it to a trans shop for a fluid and filter change. Just mention that the TV cable slipped once, and you hope you got it back in the right spot.
When you pick it up and they are sweating bullets that they screwed something up, have a nice long conversation about what they think is wrong.
Then thank them for their time, and see if you can play with it some more and get it working better.

gerardvg

I had the governor fail on my trans some years back, that kept it in first gear. That can be replaced without removing the transmission.

The TV cable... the simplest way to check it is on full throttle there should be no slack on it, you should nut be able to pull the cable out further or the cable should not deflect much when you press it with your finger. (it is also self adjusting)

The TV cable does not adjust your shift points, think of it as a transmission pressure adjuster, soft shifts at low throttle and harder shifts at full throttle. If it is too loose you will have a lot of slippage and that can burn the transmission clutches very quickly within minutes or an hour requiring a rebuild.

cimchazz1

That's funny. I like it. The only problem is, around here they would drop the pan and tell me it needs to be rebuilt, then they would make sure they were right, if you know what I mean. I really should keep pulling that old fluid out and replacing it, though. Maybe I can install a drain plug in the pan somehow??
This car sat alot, I've had a number of cars that sat a long time, and what I've found is that when you start using them again, some of the systems that aren't working properly will start to work again (magically) after awhile, and some never come back.I like to let things settle out before I start jumping into repairs. This car pretty much sat for 2 years, was driven 2000 miles, then sat another 2 years with the trans issue. I need to get it out on the road and see what it's going to do. I'm am wondering if someone changed the spring in the TV and replaced the cable (cable looks relatively new) and the spring is so strong that when I am trying to adjust the cable, the TV piston stops moving before it reaches the end if it's travel (can't compress the spring) and the cable casing pulls out farther instead (when I do the adjustment), which gives me low pressure. I really need to find someone who knows how this stuff works.

cimchazz1

Thanks, the cable is tight at WOT when I adjust as I am supposed to, but I am wondering if somebody changed something in the trans that makes it hard to adjust this way. Just a thought, if someone put a stronger return spring on the TV piston, wouldn't the button adjuster at the "carb" allow the whole cable to pull farther through the adjuster more clicks if it took less force to do that than pulling against the stiffer TV spring? I am thinking the regular process becomes less reliable when things start to get modified. Guess I really need to find out how to check the pressure next.

cimchazz1

Thanks for the info. With what I did today, if anything I should be running higher pressure, I would guess. Any idea what the effect of high pressure would have on the trans? BTW, I noticed the cable is routed under the trans dipstick bracket, would that affect anything? I think it has been replaced, it's real clean and shiny. I'm thinking I need to check to make sure it is bolted to the trans, and replace the TV spring and piston so I know what's in there.

ddahlgren

Yours drives like my 91 firm but not hash shifts around 2400 indicated but my tach reads a bit high as most do. There are a lot of threads on fixing that though i have not bothered with mine. Mine shifts at around 14 to 17, 32 to 34 and 45 to 47 with normal driving.

cimchazz1

Thanks, both sound like good suggestions. But before I drop the pan again, is there a way I can measure the cable travel to determine if the plunger is moving the right distance? And if someone has put a longer or stronger TV spring in, during the cable set process, is it possible the plunger could stop moving and the cable would pull out too far instead? If I drop the pan, I will probably have to replace the plunger and spring, just to be sure I know what's in there. I might even replace the TV cable just to be sure I have the correct one, unless they are common.

Maybe the cable isn't secured properly to the trans, depending on who changed it. But I'm really curious as to why it was changed, could be a used trans someone put in, you never know with used cars. I know you have to be a pretty good detective to sort through this stuff to root cause it.

Cliff Harris

The TV cable connects to a cam in the trans that moves the TV valve. There is a spring on the cam linkage and you should be able to feel that spring tension at the throttle body, even when the throttle blades are closed. The spring is pretty weak, so there is not much tension there, just enough to keep the cable tight.

I think the TV cable would leak if it's not properly secured to the trans. I don't think it's possible to get to it with the front exhaust in place. It's a 10mm bolt, if you get that far.

Higher pressures make the frictions clamp tighter -- a good thing. It prevents slipping, which can burn the frictions. A classic symptom of a poorly adjusted TV cable is burned frictions because of low pressure. These cars make a lot of torque at low RPM so you need to have the TV cable adjusted correctly to get the pressure the trans needs.

After having a bad experience with aftermarket trans parts (see below), I wouldn't trust something as critical as the TV cable. I don't know for sure, but I don't think the one with the square button is a GM part. Just for reference, I was given a 700r4 that had burned 3-4 clutches. It had a square TV cable button.

See what I went through with my shifter cable:

http://forums.corvetteforum.com/c4-t...ally-ugly.html

cimchazz1

Thanks, interesting. If nothing else is wrong with mine, I am guessing the outside cable housing could be too long, but no one else is coming forward with an issue similar to mine yet, so I can't really tell if the cable is the issue, but I agree it is probably an aftermarket part, and I usually don't have good luck with them, either.
So far, I haven't found any markings on it. I think I can feel the cam spring and then there is a definate increase in cable tension as I pull it against the plunger spring. That is the travel I would like to find a measurement for. I am assuming I can determine how far the plunger is moving from this. I'm sure someone out there knows exactly what I am having an issue with and has been through this, so let's see if anyone speaks up. Thanks.

Cliff Harris

Here's a ton of information on the TV valve and cable from Bow Tie Overdrives:

http://www.tvmadeez.com/article/index.php

There is a broken link at the end of that series of web pages and the last page doesn't exist.

From what I can see from the diagrams and such, the TV valve moves to a maximum pressure position (the flat part of the cam), but it's not at all clear to me how much throttle valve movement it takes to get to that point. I'm also not clear on what happens when the cam reaches the maximum position. It seems to me the cable would bind. I guess it does bind and that's what pulls the cable sheath out of the locking thingy when you do the adjustment.

I have heard of people that had the inner steel cable part stretch (leesvet is one).

cimchazz1

Thanks for the response, it makes sense. I will take a look at the link.
I agree that the cable probably is set by the throttle after the valve stops moving, so one question I have, since my cable seems like it is pulled out too far to get the pressure I need to shift after I "set" it, is if someone has put a spring "under" the valve that makes the valve harder to move to the end of it's travel, is it possible the cable adjuster will let the cable casing pull through it too far (thereby giving me not enough pressure at idle and low speeds, calibration off) before the valve is where it should be? When I disconnect the cable from the throttle linkage and pull it, I can feel a light resistance (maybe the lever moving up to the valve) and then the rest of the travel feels like a much stronger spring. Is that normal?

Is there a distance the cable coupling "pocket" for the throttle attach post should be from the post after the slack and the initial light lever spring travel is taken up? The problem I have with my setting is that as soon as I floor the gas pedal, I will probably pull the cable out too far again. Now I better check out that link!! Thanks

Actually, I'm adding this as an edit, but I read the link and know that my gas pedal doesn't open the throttle all the way, so I will fix that 1st, although I don't see why that matters if I set the TV by turning the throttle to WOT by hand.

cimchazz1

Tonight I popped the governor cover off and took a look. I remember the guy I bought it from telling me "it's not a governor issue, it needs to be rebuilt, according to a friend of mine who knows about transmissions". What I found was the governor gear was "apple cored" only in one spot, not all the way around like an apple core. It looks like it stopped turning, or was stuck and didn't turn at some point and the teeth sheared off in that spot? It's turning freely now, but I don't understand, looking at it, what the springs do. The "weights" just flap loose and the springs don't seem to do anything?? Anyone have any ideas why my gear would be flat in one spot only? And I'm wondering now how I got it to shift the few times I did, maybe the gear engaged for a few revolutions? Have people been successful just replacing the gear and not having a recurrence right away? Did yours have a bad gear?