• 94 Transmission Issues PLEASE HELP!
  • 94 Transmission Issues PLEASE HELP!
  • 94 Transmission Issues PLEASE HELP!
  • 94 Transmission Issues PLEASE HELP!

Thanks Thanks:  0
Likes Likes:  0
Dislikes Dislikes:  0
Results 1 to 8 of 8
  1. #1
    Towu4free
    Guest

    Default 94 Transmission Issues PLEASE HELP!

    hey guys, im hoping you can help me, my 94 vette has the 4L60E Auto trans in it, the car has 130k on it, i changed the fluid when i first got it a few months ago... heres what it does, in normal driving and acceleration it does just fine but if i launch from a dead stop at WOT it goes all the way up to the peak of the tachometer and sounds like to me its a " double shift" its hard to explain almost as if for a split second it hits Neutral then goes into gear...this may sound dumb but try to picture this as the engine..... baaaaaaaaaaaa-ba-ba-baaaaaaaaaaa any suggeestions?
    (first) (The shift) (second)

  2. #2
    Member
    Join Date
    Jan 2009
    Location
    Springfield, Illinois
    Posts
    24
    Corvette(s)
    1989 Red Convertible
    Post Thanks / Like
    Rides
    0

    Default Bad shift

    Have you tried adjusting the detent cable? This is the main adjustment for shift points based on throttle opening.

    Ron Kane
    Benchmark Corvette Service

  3. #3
    Towu4free
    Guest

    Default

    Quote Originally Posted by badglas View Post
    Have you tried adjusting the detent cable? This is the main adjustment for shift points based on throttle opening.

    Ron Kane
    Benchmark Corvette Service
    I havent tried that, i didnt think the 4l60E had one...where would i find it? i thought it was all electronically shifted...there isnt any cables coming from the throttlebody to the trans..

  4. #4
    Member
    Join Date
    Jan 2009
    Location
    Springfield, Illinois
    Posts
    24
    Corvette(s)
    1989 Red Convertible
    Post Thanks / Like
    Rides
    0

    Default shift

    My mistake, no detent cable. PCM does retard the timing on this model before each shift, could be what your feeling. I would think a valve in the valve body or its respective control servo would show problems elsewhere. One other thought; check TPS voltage at WOT and make sure it is less than 5 volts. Also watch for dead spots in the voltage while doing a full throttle sweep. May sound silly; do not try these tests on a running engine. I have found stating the obvious is safer than not.

    Ron

  5. #5
    Towu4free
    Guest

    Default

    well badglas, i really do appreciate your help, i will check that first thing tomorrow!, also i failed to mention that when i do launch it if i let off just a hair befor it gets to the top of the tach and does its "thing" is shifts ok, its almost as if its at 100% throttle it does it but if i feather it for a split second between 95-99% it shifts ok and i can mash it down to the floor and go on down the road... thank you again, and let me know what you think and ill will post my finding tomorrow

  6. #6
    Towu4free
    Guest

    Default UPDATE

    I put the vette on our snap-on modis scanner today and at full throttle it only measured 85%. So I adjusted the cable, now it reads 99%. Do you think this could have anything to do with the transmission shifting? I haven't driven it yet and the TPS censor reads .6 at idle and 4.12 at WOT. Thanks guys, and let me know.

  7. #7
    Technical Writer for Internet & Print Media
    Join Date
    Jan 2001
    Location
    CenCoast CA
    Posts
    11,785
    Corvette(s)
    71 04 12
    Post Thanks / Like
    Rides
    0

    Default

    Don't let off the gas just before the shift.

    Now that you've got 99% TPS at WOT. Road test the car by putting it in drive and accelerating with your foot on the floor. Do not lift. In first gear, the engine should go to just short of the rev limiter then upshift.
    Hib Halverson

  8. #8
    New Member
    Join Date
    Sep 2007
    Location
    Mt Vernon, Indiana
    Posts
    11
    Corvette(s)
    1994 Coupe
    Post Thanks / Like
    Rides
    0

    Default

    Quote Originally Posted by Towu4free View Post
    hey guys, im hoping you can help me, my 94 vette has the 4L60E Auto trans in it, the car has 130k on it, i changed the fluid when i first got it a few months ago... heres what it does, in normal driving and acceleration it does just fine but if i launch from a dead stop at WOT it goes all the way up to the peak of the tachometer and sounds like to me its a " double shift" its hard to explain almost as if for a split second it hits Neutral then goes into gear...this may sound dumb but try to picture this as the engine..... baaaaaaaaaaaa-ba-ba-baaaaaaaaaaa any suggeestions?
    (first) (The shift) (second)

    Mine does/did the exact same thing! Kept messing with it and nothing helped. I ended up changing the trans fluid and then it would slip so bad it was undrivable. Not sure if the two are related, but maybe the trans has seen better days. I ended up rebuilding it in the end.

Similar Threads

  1. Help! Update: '94 LT1 Hard Starting Issues??
    By Donne Trav in forum C4 Technical and Performance
    Replies: 0
    Last Post: 10-05-08, 09:55 AM
  2. '94 Alignment Issues: Bumper/Hood.etc.??
    By Donne Trav in forum C4 General Discussion
    Replies: 6
    Last Post: 09-07-08, 09:17 PM
  3. Replies: 0
    Last Post: 12-14-07, 10:29 AM
  4. 2008 - Tremec TR-6060 Manual transmission
    By Runge_Kutta in forum C6 General Discussion
    Replies: 3
    Last Post: 10-21-06, 01:09 AM
  5. Interesting GM Patents
    By Runge_Kutta in forum C6 Technical and Performance
    Replies: 12
    Last Post: 10-05-04, 04:29 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •