Low voltage on start up

Discussion in 'General Discussion' started by Flat4bo, Aug 2, 2017.

Car Parts
  1. Flat4bo

    Flat4bo Full Access Member

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    I have noticed latley when my truck sits for a week or so and I start it the "check guage" light comes on and the voltage guage is lower than it should be. It doesnt happen everytime either. Once I hit the gas the guages jumps up and the "check guage" light goes away. I have had an underdrive pulley on for a few months but I did recently install a jtvsp throttle body.

    The idle does not seem low but could the throttle body messed with the idle just enough for it get mad?

    Is this a product of the underdrive pulley? I have noticed since the underdrive pulley the belt will squeal for about one second after starting sometimes.


    If this is check guage voltage issue is not a big deal I wont sweat it because it only does it sometimes and disapears once you tap the gas. Just want to make sure.
     
  2. rbabody

    rbabody Full Access Member

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    1st check your battery. For the belt make sure it's clean and dry then check your tensioner.
     
  3. Chuck B

    Chuck B Full Access Member

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    Load test your battery.
     
  4. Flat4bo

    Flat4bo Full Access Member

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    The battery is about 6 months old and the Belt came with the new UD pulley. There is a chance that this is happening only after it rains. I know that hood scoop funnels water on the front of the engine. Maybe the belt is slipping slightly until it dries itself.
     
  5. VPRPWRD

    VPRPWRD VTCoA Ring Leader Supporting Member

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    That is exactly what is happening. Happens every time I wash my truck.
     
  6. Flat4bo

    Flat4bo Full Access Member

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    Ok cool so nothing to worry about? Does your "check gauge" light and voltage gauge read low as well?
     
  7. IronAffliction

    IronAffliction Full Access Member

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    Yes happens to me. I live in wa it rains alot so when my truck sits outside the belt gets wet and slips. Ya engine light comes on then back off once the belt stops slipping
     
  8. trussman

    trussman Active Member

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    My issue was resolved after my crank pulley removed itself from the crank shaft and when I replaced the pulley.
     
  9. Flat4bo

    Flat4bo Full Access Member

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    oem or aftermarket pulley? what happened?
     
  10. trussman

    trussman Active Member

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    OEM. Crank Bolt backed out.
     
  11. VENOMOUS1 RACING

    VENOMOUS1 RACING Has Left the Room - Banned from VTCOA!

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    Have someone start it while you watch everything. See if you see a pulley that doesn't initially spin. Idler and tensioner pulley are common to lock up. Correct belt size for Pulley would be next question. Remove belt and spin all accessories listening and feeling for noise/roughness