Auto Tranny shifting stinks!!!
Thread Starter
Intermediate
Joined: Mar 2004
Posts: 48
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From: Woodhaven MI
Auto Tranny shifting stinks!!!
I bought my car last year and am slowly fixing it up....One of my pet peeves is the trans. While driving down side streets in 'D'rive the trans will shift into 3rd when at about 25mph and then it feels like it's shifting into OD and the car starts to shutter. If I manually put it into 3rd or 2nd it smooths out. The guy I bought it off of (a real TOOL!) said he had the tranny rebuilt but didn't get into any specifics. Any thougths?
Oh and by the way....You guys are great. I've been reading alot of other threads and it's helped me with my vette just from reading them!!!
[Modified by TheShield, 10:42 PM 3/6/2004]
Oh and by the way....You guys are great. I've been reading alot of other threads and it's helped me with my vette just from reading them!!!
[Modified by TheShield, 10:42 PM 3/6/2004]
Threadkiller
Joined: Jan 2002
Posts: 15,306
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From: Long Island, NY
Cruise-In 9-10 Veteran
St. Jude Donor '05-'06-'07-'08-'09
Re: Auto Tranny shifting stinks!!! (TheShield)
It's not supposed to go into 4th until it gets to about 43mph. If it is, something is wrong.
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Re: Auto Tranny shifting stinks!!! (TheShield)
Try re-adjusting the TV cable first to see if that helps any....On the drivers side of your plenum behind where the throttle cables are mounted to the plenum there is a black box where the TV (transmission kickdown) cable goes through. Press in on this box with your finger, and at the same time grab the cable housing behind the box and pull it towards the windshield as far as it will go, then let off the button. Then manually open the throttle body blades fully a few times and you should hear the TV cable snap into its newly adjusted position.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Auto Tranny shifting stinks!!! (Wheelman)
If it still upshifts too early after that reset, move the TV cable button a click or two away from the firewall.
This will raise and soften the part throttle shifts. Don't over do it though as this will lower line pressure and dropping line pressure too much can accelerate tranny wear.
This will raise and soften the part throttle shifts. Don't over do it though as this will lower line pressure and dropping line pressure too much can accelerate tranny wear.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Re: Auto Tranny shifting stinks!!! (TheShield)
[QUOTE]While driving down side streets in 'D'rive the trans will shift into 3rd when at about 25mph and then it feels like it's shifting into OD and the car starts to shutter. If I manually put it into 3rd or 2nd it smooths out. [QUOTE]
:iagree: With the previous posts. Re-adjust your TV Cable. The closer you move it to the firewall the later it shifts. Give that a try and tell us what happens.
About the "Shutter" do you feel it after the trans feels like it hits OD and you get on the accelerator? If so, and if re-adjusting the TV Cable did not fix the "Shutter" I can tell you what caused it on my 86. It drove me nuts for 2 days till I found out what it was. :thumbs:
:iagree: With the previous posts. Re-adjust your TV Cable. The closer you move it to the firewall the later it shifts. Give that a try and tell us what happens.
About the "Shutter" do you feel it after the trans feels like it hits OD and you get on the accelerator? If so, and if re-adjusting the TV Cable did not fix the "Shutter" I can tell you what caused it on my 86. It drove me nuts for 2 days till I found out what it was. :thumbs:
Thread Starter
Intermediate
Joined: Mar 2004
Posts: 48
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From: Woodhaven MI
Re: Auto Tranny shifting stinks!!! (86PACER)
Ok guys....I'll give it a try this weekend....still in storage at parents barn. Just to add to my post. Now that I think about it, it does sound like the TV cable needs to be adjusted. Normal driving it shifts way too soon. When I get on it the tranny holds the shifts a lot longer. I'll let ya know what happens!!! After that it's time for the Tech1 to figure out which injector is bad! By the way, I'm new here so any suggestions on how I put pic's of the vette in posts or my bio would be appreciated. Thanks again!!!! :party:
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
Re: Auto Tranny shifting stinks!!! (TheShield)
This shutter, does it occur right about 1,000-1,200 RPM at those low speeds?
If so, try to see if in park or neutral - you bring the RPM up to that range above and see if it is still shuttering. The reason I mention this was I had a similar condition. Driving locally in the 35-40mph range and it kicks over to OD, it felt like shutter but was an engine condition. Pulled the throttle body, clean and replaced it with a new IAC and finallyt that condition went away. It drove me nuts, and started after the Opti was replaced, dealer couldn't find a code or anything wrong, but still it behaved that way, I replaced plugs and wires. Still the same, finally pulled the TB and that solved the problem.
See pictures... this might be your problem as well. Something to consider.
As far as shifting, mine shifts quick out of first, seconds keeps you tight in the seat and if you back off right away to hold say 40, it will shift to third then right to OD and settle in.
If so, try to see if in park or neutral - you bring the RPM up to that range above and see if it is still shuttering. The reason I mention this was I had a similar condition. Driving locally in the 35-40mph range and it kicks over to OD, it felt like shutter but was an engine condition. Pulled the throttle body, clean and replaced it with a new IAC and finallyt that condition went away. It drove me nuts, and started after the Opti was replaced, dealer couldn't find a code or anything wrong, but still it behaved that way, I replaced plugs and wires. Still the same, finally pulled the TB and that solved the problem.
See pictures... this might be your problem as well. Something to consider.
As far as shifting, mine shifts quick out of first, seconds keeps you tight in the seat and if you back off right away to hold say 40, it will shift to third then right to OD and settle in.
Thread Starter
Intermediate
Joined: Mar 2004
Posts: 48
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From: Woodhaven MI
Re: Auto Tranny shifting stinks!!! (93JetJocky)
Thanks Jet. :thumbs: ...That sounds 99% like my problem, although I'm going to check the TV cable also....I bought the 'ole '86 last spring and did a complete tune up on it....nothing. I have to take the intake and runners off anyways to get to a bad injector so I'll hit the TB while I'm at it....On another note I thought about porting the runners and plenum but don't want to frig it up....Is it hard to do....I read a members site on how-to, just a little leary. :skep:
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Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Re: Auto Tranny shifting stinks!!! (TheShield)
On another note I thought about porting the runners and plenum but don't want to frig it up....Is it hard to do....I read a members site on how-to, just a little leary. :skep:
Came out very well. :thumbs: