+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 16

Thread: Any Ideas?

  1. #1

    Any Ideas?

    Sometimes the the motor will be turning 2100rpm doing say 70mph and then the after 5 miles down the road or just a mile down the road(just depends on when it wants to do it) it will jump up to 2300rpm in order to run the 70mph i was just running...im thinking its the torque converter locking in and out, but im not sure...what do yall think?...and how to fix this problem?

    it was doing this when the 4.3 was bolted to it and still doing it with the 5.3
    1999 rcss/2002 5.3, Ls1 cam, Ls6 intake manifold, Ported TB, NelsonPerformance tune, CAI, MSD 8.5s, Sanderson shorties, Magnaflow X-pipe, Maganflow 2in2out muffler(no cats), FLT lvl4, Yank 3600, B&M tranny cooler, e-fans, 2/3 drop, Truetrac, Trickflow cover, 3.42 gears, Caltracs, A.R. Irocs 18"x8", NS-2s(245/40/18), Nitto 555s(275/45/18) two JL 10s, 2" cowl hood, SS mirrors, SS bumper cover, step shavers, and Alot from Current Performance

  2. #2
    Join Date
    Sep 2008
    Location
    California
    Posts
    60
    I would guess it is the torque converter doing something, what that is I have no idea for sure. I would guess it is what you think it is. As long as it is not slipping in other gears.

    I would check it by running in 3rd instead of drive, set the cruise and if it is slipping up a hill you will be able to see it. If it is the torque converter locking and unlocking then you will see the same jump in RPM's only will be more noticable and will probably be a longer jump in the RPM's.

    Have fun!
    1998 Silverado Z-71 Ext Cab. 5.7L Descreened MAF, K&N direct replacment, 32x11.5 R15 AT's,Posi rear end, True duel w/Magnaflows, Sub woofer setup, Remote starter.

  3. #3
    Join Date
    Jul 2008
    Posts
    329
    It's your TC locking/unlocking. Easy fix - have Nelson tweak your tune.

  4. #4
    Join Date
    Apr 2005
    Posts
    4,229
    Quote Originally Posted by Madd Maxx View Post
    It's your TC locking/unlocking. Easy fix - have Nelson tweak your tune.
    +1

    Mine did the same thing, except at 55 mph.
    Gone, but not forgotten!

  5. #5
    Join Date
    Mar 2003
    Location
    San Marcos Texas
    Posts
    4,393
    Maybe your brake switch is too sensitive? If you hit the brakes the converter will unlock.
    2006 Superior Blue Trailblazer SS AWD, Stock as a rock

    Sold: 2002 GMC Sportside Denali front end with a 2002 LS1, FLT level 5, Yank 2600, Trick Turbo, T76, Nelson intercooler, 60LB injectors, Warbro fuel pump, Eaton locker, Magnaflow, 3.42, Nelson Performance Tuning (speed density).

    Sold: 1981 GMC LB RC 1500 2002 4.8L 4L60E 12 bolt 3.73 Richmond Lock Right AC PS Nelson Performance tuning

  6. #6
    Join Date
    Mar 2003
    Location
    San Antonio, TX
    Posts
    11,038
    The key to his issue was, it was doing it with the 4.3L.
    if it's the tune, we can fix it, but it might not be.

  7. #7
    Join Date
    Aug 2005
    Location
    St. Anthony, Indiana
    Posts
    1,592
    Quote Originally Posted by GMCwantsLS1 View Post
    Maybe your brake switch is too sensitive? If you hit the brakes the converter will unlock.
    x2

  8. #8
    Join Date
    Aug 2008
    Location
    North Texas
    Posts
    12,078
    +3 on the brake switch adjustment.

  9. #9
    how to adjust break switch sensor?
    1999 rcss/2002 5.3, Ls1 cam, Ls6 intake manifold, Ported TB, NelsonPerformance tune, CAI, MSD 8.5s, Sanderson shorties, Magnaflow X-pipe, Maganflow 2in2out muffler(no cats), FLT lvl4, Yank 3600, B&M tranny cooler, e-fans, 2/3 drop, Truetrac, Trickflow cover, 3.42 gears, Caltracs, A.R. Irocs 18"x8", NS-2s(245/40/18), Nitto 555s(275/45/18) two JL 10s, 2" cowl hood, SS mirrors, SS bumper cover, step shavers, and Alot from Current Performance

  10. #10
    Join Date
    Aug 2008
    Location
    North Texas
    Posts
    12,078
    Twist slightly to disengage then pull towards pedal. Relock it and don't pull it up so far that the pedal pushes the whole thing back breaking the retainer.

+ Reply to Thread

Posting Permissions

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