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  1. #1

    Default 98 vortec 350 timing.

    I just went thru the trouble of replacing a faulty intake manifold gasket.

    So far not leaks, and all of the bolts for disassebly have been accounted for.

    The problem. Truck is hard to start and won't idle. We fiddled with the distributor for awhile, but have gotten no where. Doing some searching it seems it should be all electronic. Distributor was previously marked, so I set them back in the same location.

    What could be causing a rough start no idle? It seems with the slotted gear on the bottom the rotor itself can only go in one of two different ways, and I'm pretty sure we don't have it backward.


  2. #2
    Jr. Apprentice
    Join Date
    Jun 2010
    Augusta, GA (for now)


    The slot at the bottom runs your oil pump. the gear a couple inches up mesh with the cam and mechanicaly turn your rotor. you may have it off one tooth. You need to get a timming light and time the engine.

  3. #3


    "Timing" is set with a scan tool on these engines. It's called phase angle. Does it run at all?
    When you hear hoofbeats, look for horses not zebras.

  4. #4


    We tried timing with a light, and found no success, that is when I found it is supposed to be all electronic.
    We adjusted the distributor clockwise, and now she idles with no gas input, but rough. We were able to let it run for 15 minutes fine.

    As soon as I put it in gear to test drive, it died. Truck won't take any load.

    So are you saying the gear that meshes with the cam can turn independantly of the slot on the bottom that turns the oil pump?
    Last edited by Kraziken; 06-06-2010 at 09:25 PM.

  5. #5


    Found the problem, it was timing, and we were a few teeth off. Now onto a new problem.

  6. #6
    Jr. Apprentice
    Join Date
    Jan 2010
    Bountiful, Utah


    Were you able to get it timed by yourself? Mine was dead on "we thought" and ran fine but still threw code P1345 which is related to timing being off.

    I had mine hooked to a scantool and it was 18 degrees off. Timed it using the scantool and the light was off immediately. Damn computer controlled timing.
    96 Tahoe
    Flat tops
    LT4 cam
    2200 Stall
    Built trans
    3" exhuast
    Hypertech programmer
    255/70/17 BFG mud terrains

    And after all that it is still SLOW!!!!

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