1993 Pontiac Grand Am transmission wont shift

1993 PONTIAC GRAND AM
312,000 MILES • 6 CYL • FWD • AUTOMATIC
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JOHNE317
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I took my car in to the mechanic because the water pump blew and when i got it back, it wont shift. Mechanic replaced the water pump and serpentine belt, and car starts and runs great. I checked the TV cable and it was very worn, so i removed it and drove around to see if for some reason that was why but the problem remains. I have checked the linkage and it seems to be fine, car starts in park and neutral, reverse and drive engage and neutral is normal. Does not move in park so the transmission is shifting manually, but the thing wont go out of 1st! Fluid level is in operating range, actually a little over full... could that be the problem? I have been running it at the current fluid level for 12k miles so im just at a loss.
Nov 7, 2009 at 9:36 PM
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PEAR69
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Did the mechanic test drive the car? If so, wouldn't of he or she detect this problem??
A worn out TV cable will not allow the transmission to properly operate --- driving around with it disconnected will damage the transmission..Try replacing the TV cable..
Nov 7, 2009 at 9:56 PM
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JOHNE317
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Yes, the mechanic test drove it, and yes he did identify the problem. The tv cable is necessary to have the transmission operate completely, however with the tv cable installed the transmission will not shift, and with it off it will not shift... so im not thinking the tv is the problem... I dont know if the transmission is vacuum controlled or electronic... it could be a couple of things i guess, i just dont know where to start.
Nov 7, 2009 at 10:32 PM
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PEAR69
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Start by replacing the TV Cable. This cable tells the transmission and computer, how far the throttle body is opened. If it "very badly" worn, it will give false readings to the computer, which will in turn, not tell the transmission to up or down shift. Your transmission is electonicly shifted, but if you have a vacuum leak - it will affect the engine which will affect the transmission....
Nov 7, 2009 at 11:26 PM
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JOHNE317
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so i replaced the tv cable with a brand new one from GM and nothing... still the same problem. very frustrating.
Nov 13, 2009 at 9:55 PM
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PEAR69
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Assuming that the tv cable is adjusted properly -- When was the last time transmission fluid and filter was changed? Are there 312000 miles on this transmission? It should have been changed about 5 times so far. Did the transmission act like this before you took it to the mechanic for a water pump? Why is there too much fluid in the transmission?
Nov 14, 2009 at 8:30 AM
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JOHNE317
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regarding the adjustment of the tv cable... there is a button type ... thing... on the cable. from what i understand i need to have the throttle all the way in the closed position and then press the button... but it doesnt seem to do anything. is there a different adjustment?
Nov 14, 2009 at 10:38 AM
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PEAR69
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First, verify that it is hooked to the transmission properly. Then make sure that the throttle is at the idle position (closed). Then hook it up and push the button. It should only adjust about .07 of an inch -- not much..If the TV cable doesn't fix the problem, the control valve or something else inside of the tranny could be bad.
What about the other questions I asked?
If the reason that the tranny fluid is over filled is because that the fluid leaks (or at some point it leaked out), and the low fluid level was discovered too late, then you may want to consider rebuilding your tranny. Transmission fluid does not get consumed like engine oil, you should never have to add any.
Nov 14, 2009 at 7:57 PM