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97 2500 vortec 350 timing issue

Discussion in 'Chevy Trucks' started by chris694205, Jan 9, 2011.

  1. chris694205

    chris694205 Senior Member
    Messages: 175

    hello guys,

    my older plow truck has a vortec 350. i recently had the motor replaced with a used aftermarket engine. Everything works great except the code reader says that the timing is advanced 24 degrees. It is fairly hard to start when warm and seems to be lacking a little power but the service engine light is off. My question is, Is 26 degrees far enough out to the point where i would have to pull the distributor out and move it one tooth or do you think i could twist the cap enough to solve the problem?
     
  2. got-h2o

    got-h2o 2000 Club Member
    Messages: 2,439

    You will have to correct it with a scan tool. It's probably that far out b/c it's over correcting itself for one reason or another.
     
  3. chris694205

    chris694205 Senior Member
    Messages: 175

    hmm. i didnt know you could correct it with a scan tool
     
  4. 2COR517

    2COR517 PlowSite Fanatic
    Messages: 7,115

    I think he meant use a scan tool to read the phase angle as you adjust the distributor.
     
  5. PowersTree

    PowersTree Senior Member
    Messages: 586

    You need to put it on a scanner after engine replacement. You need to reset the crank variation, and timing via the tool. I recommended taking it to a mechanic that is familiar with the system. Its very easy, once you know how to do it.

    If you really wanna liven it up, get a custom program wrote. You can free up 70hp through the computer.
     
  6. woodchuck2

    woodchuck2 Senior Member
    Messages: 304

    Yup. need a scan tool to ring it back withen spec. Should be at 0deg but it can be withen +2 deg or -2 deg before the SES sets a code. It will run up to 29deg out before the PCM cannot compensate. Instead of pull the dist to reset just move all the wires one stud on the cap.
     
  7. chris694205

    chris694205 Senior Member
    Messages: 175

    why wouldnt it be setting the SES light right now though? I dont get it
     
  8. PowersTree

    PowersTree Senior Member
    Messages: 586

    Because its close enough to specs to not set the light. If you've changed the motor, you need to get it on a scan tool.

    Set the crank variation, and timing. It'll probably solve your issues. If not, you'll at the minimum get the motor tuning corect. I've replaced a few of these engines. Research it at fsc.com if you wanna read it from the vortec gurus.
     
  9. chris694205

    chris694205 Senior Member
    Messages: 175

    hey powerstree, do you really think a tune will help this old girl out?? I have been shopping around for a tune for my 8.1 which im real excited about but i wasnt sure about my old 5.7
     
  10. PowersTree

    PowersTree Senior Member
    Messages: 586

    Supposedly, Blackbear can open up on average 45 HP, just by turning off torque mgmt. Blackbear is the best GM tuner out there.